diff --git a/dlls/jscript/activex.c b/dlls/jscript/activex.c
index 39515081ed1..2dd803801e9 100644
--- a/dlls/jscript/activex.c
+++ b/dlls/jscript/activex.c
@@ -138,7 +138,7 @@ static IUnknown *create_activex_object(script_ctx_t *ctx, const WCHAR *progid)
     return obj;
 }
 
-static HRESULT ActiveXObject_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT ActiveXObject_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     IDispatch *disp;
@@ -164,7 +164,7 @@ static HRESULT ActiveXObject_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
         return E_NOTIMPL;
     }
 
-    hres = to_string(ctx, argv, ei, &progid);
+    hres = to_string_jsval(ctx, argv[0], ei, &progid);
     if(FAILED(hres))
         return hres;
 
diff --git a/dlls/jscript/array.c b/dlls/jscript/array.c
index f557fcf8fc9..00911933d53 100644
--- a/dlls/jscript/array.c
+++ b/dlls/jscript/array.c
@@ -62,7 +62,7 @@ static inline ArrayInstance *array_this(vdisp_t *jsthis)
 static HRESULT get_length(script_ctx_t *ctx, vdisp_t *vdisp, jsexcept_t *ei, jsdisp_t **jsthis, DWORD *ret)
 {
     ArrayInstance *array;
-    VARIANT var;
+    jsval_t val;
     HRESULT hres;
 
     array = array_this(vdisp);
@@ -75,12 +75,12 @@ static HRESULT get_length(script_ctx_t *ctx, vdisp_t *vdisp, jsexcept_t *ei, jsd
     if(!is_jsdisp(vdisp))
         return throw_type_error(ctx, ei, JS_E_JSCRIPT_EXPECTED, NULL);
 
-    hres = jsdisp_propget_name(vdisp->u.jsdisp, lengthW, &var, ei);
+    hres = jsdisp_propget_name(vdisp->u.jsdisp, lengthW, &val, ei);
     if(FAILED(hres))
         return hres;
 
-    hres = to_uint32(ctx, &var, ei, ret);
-    VariantClear(&var);
+    hres = to_uint32_jsval(ctx, val, ei, ret);
+    jsval_release(val);
     if(FAILED(hres))
         return hres;
 
@@ -90,15 +90,12 @@ static HRESULT get_length(script_ctx_t *ctx, vdisp_t *vdisp, jsexcept_t *ei, jsd
 
 static HRESULT set_length(jsdisp_t *obj, jsexcept_t *ei, DWORD length)
 {
-    VARIANT var;
-
     if(is_class(obj, JSCLASS_ARRAY)) {
         ((ArrayInstance*)obj)->length = length;
         return S_OK;
     }
 
-    num_set_int(&var, length);
-    return jsdisp_propput_name(obj, lengthW, &var, ei);
+    return jsdisp_propput_name(obj, lengthW, jsval_number(length), ei);
 }
 
 static WCHAR *idx_to_str(DWORD idx, WCHAR *ptr)
@@ -116,7 +113,7 @@ static WCHAR *idx_to_str(DWORD idx, WCHAR *ptr)
     return ptr+1;
 }
 
-static HRESULT Array_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     ArrayInstance *This = array_from_vdisp(jsthis);
@@ -132,7 +129,7 @@ static HRESULT Array_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
         DWORD i;
         HRESULT hres;
 
-        hres = to_number(ctx, argv, ei, &len);
+        hres = to_number_jsval(ctx, argv[0], ei, &len);
         if(FAILED(hres))
             return hres;
 
@@ -159,19 +156,19 @@ static HRESULT Array_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 
 static HRESULT concat_array(jsdisp_t *array, ArrayInstance *obj, DWORD *len, jsexcept_t *ei)
 {
-    VARIANT var;
+    jsval_t val;
     DWORD i;
     HRESULT hres;
 
     for(i=0; i < obj->length; i++) {
-        hres = jsdisp_get_idx(&obj->dispex, i, &var, ei);
+        hres = jsdisp_get_idx(&obj->dispex, i, &val, ei);
         if(hres == DISP_E_UNKNOWNNAME)
             continue;
         if(FAILED(hres))
             return hres;
 
-        hres = jsdisp_propput_idx(array, *len+i, &var, ei);
-        VariantClear(&var);
+        hres = jsdisp_propput_idx(array, *len+i, val, ei);
+        jsval_release(val);
         if(FAILED(hres))
             return hres;
     }
@@ -183,7 +180,6 @@ static HRESULT concat_array(jsdisp_t *array, ArrayInstance *obj, DWORD *len, jse
 static HRESULT concat_obj(jsdisp_t *array, IDispatch *obj, DWORD *len, jsexcept_t *ei)
 {
     jsdisp_t *jsobj;
-    VARIANT var;
     HRESULT hres;
 
     jsobj = iface_to_jsdisp((IUnknown*)obj);
@@ -196,12 +192,10 @@ static HRESULT concat_obj(jsdisp_t *array, IDispatch *obj, DWORD *len, jsexcept_
         jsdisp_release(jsobj);
     }
 
-    V_VT(&var) = VT_DISPATCH;
-    V_DISPATCH(&var) = obj;
-    return jsdisp_propput_idx(array, (*len)++, &var, ei);
+    return jsdisp_propput_idx(array, (*len)++, jsval_disp(obj), ei);
 }
 
-static HRESULT Array_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *ret;
@@ -216,15 +210,13 @@ static HRESULT Array_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 
     hres = concat_obj(ret, jsthis->u.disp, &len, ei);
     if(SUCCEEDED(hres)) {
-        VARIANT *arg;
         DWORD i;
 
         for(i=0; i < argc; i++) {
-            arg = argv+i;
-            if(V_VT(arg) == VT_DISPATCH)
-                hres = concat_obj(ret, V_DISPATCH(arg), &len, ei);
+            if(is_object_instance(argv[i]))
+                hres = concat_obj(ret, get_object(argv[i]), &len, ei);
             else
-                hres = jsdisp_propput_idx(ret, len++, arg, ei);
+                hres = jsdisp_propput_idx(ret, len++, argv[i], ei);
             if(FAILED(hres))
                 break;
         }
@@ -243,7 +235,7 @@ static HRESULT Array_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 static HRESULT array_join(script_ctx_t *ctx, jsdisp_t *array, DWORD length, const WCHAR *sep, jsval_t *r, jsexcept_t *ei)
 {
     BSTR *str_tab, ret = NULL;
-    VARIANT var;
+    jsval_t val;
     DWORD i;
     HRESULT hres = E_FAIL;
 
@@ -262,18 +254,19 @@ static HRESULT array_join(script_ctx_t *ctx, jsdisp_t *array, DWORD length, cons
         return E_OUTOFMEMORY;
 
     for(i=0; i < length; i++) {
-        hres = jsdisp_get_idx(array, i, &var, ei);
+        hres = jsdisp_get_idx(array, i, &val, ei);
         if(hres == DISP_E_UNKNOWNNAME) {
             hres = S_OK;
             continue;
         } else if(FAILED(hres))
             break;
 
-        if(V_VT(&var) != VT_EMPTY && V_VT(&var) != VT_NULL)
-            hres = to_string(ctx, &var, ei, str_tab+i);
-        VariantClear(&var);
-        if(FAILED(hres))
-            break;
+        if(!is_undefined(val) && !is_null(val)) {
+            hres = to_string_jsval(ctx, val, ei, str_tab+i);
+            jsval_release(val);
+            if(FAILED(hres))
+                break;
+        }
     }
 
     if(SUCCEEDED(hres)) {
@@ -339,7 +332,7 @@ static HRESULT array_join(script_ctx_t *ctx, jsdisp_t *array, DWORD length, cons
 }
 
 /* ECMA-262 3rd Edition    15.4.4.5 */
-static HRESULT Array_join(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_join(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
@@ -355,7 +348,7 @@ static HRESULT Array_join(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
     if(argc) {
         BSTR sep;
 
-        hres = to_string(ctx, argv, ei, &sep);
+        hres = to_string_jsval(ctx, argv[0], ei, &sep);
         if(FAILED(hres))
             return hres;
 
@@ -369,11 +362,11 @@ static HRESULT Array_join(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
     return hres;
 }
 
-static HRESULT Array_pop(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_pop(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
-    VARIANT val;
+    jsval_t val;
     DWORD length;
     HRESULT hres;
 
@@ -395,30 +388,30 @@ static HRESULT Array_pop(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned
 
     length--;
     hres = jsdisp_get_idx(jsthis, length, &val, ei);
-    if(SUCCEEDED(hres)) {
+    if(SUCCEEDED(hres))
         hres = jsdisp_delete_idx(jsthis, length);
-    } else if(hres == DISP_E_UNKNOWNNAME) {
-        V_VT(&val) = VT_EMPTY;
-        hres = S_OK;
-    } else
+    else if(hres == DISP_E_UNKNOWNNAME)
+        val = jsval_undefined();
+    else
         return hres;
 
     if(SUCCEEDED(hres))
         hres = set_length(jsthis, ei, length);
 
     if(FAILED(hres)) {
-        VariantClear(&val);
+        jsval_release(val);
         return hres;
     }
 
     if(r)
-        hres = variant_to_jsval(&val, r);
-    VariantClear(&val);
+        *r = val;
+    else
+        jsval_release(val);
     return hres;
 }
 
 /* ECMA-262 3rd Edition    15.4.4.7 */
-static HRESULT Array_push(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_push(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
@@ -433,7 +426,7 @@ static HRESULT Array_push(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
         return hres;
 
     for(i=0; i < argc; i++) {
-        hres = jsdisp_propput_idx(jsthis, length+i, argv+i, ei);
+        hres = jsdisp_propput_idx(jsthis, length+i, argv[i], ei);
         if(FAILED(hres))
             return hres;
     }
@@ -447,12 +440,12 @@ static HRESULT Array_push(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
     return S_OK;
 }
 
-static HRESULT Array_reverse(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_reverse(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
     DWORD length, k, l;
-    VARIANT v1, v2;
+    jsval_t v1, v2;
     HRESULT hres1, hres2;
 
     TRACE("\n");
@@ -470,28 +463,28 @@ static HRESULT Array_reverse(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsi
 
         hres2 = jsdisp_get_idx(jsthis, l, &v2, ei);
         if(FAILED(hres2) && hres2!=DISP_E_UNKNOWNNAME) {
-            VariantClear(&v1);
+            jsval_release(v1);
             return hres2;
         }
 
         if(hres1 == DISP_E_UNKNOWNNAME)
             hres1 = jsdisp_delete_idx(jsthis, l);
         else
-            hres1 = jsdisp_propput_idx(jsthis, l, &v1, ei);
+            hres1 = jsdisp_propput_idx(jsthis, l, v1, ei);
 
         if(FAILED(hres1)) {
-            VariantClear(&v1);
-            VariantClear(&v2);
+            jsval_release(v1);
+            jsval_release(v2);
             return hres1;
         }
 
         if(hres2 == DISP_E_UNKNOWNNAME)
             hres2 = jsdisp_delete_idx(jsthis, k);
         else
-            hres2 = jsdisp_propput_idx(jsthis, k, &v2, ei);
+            hres2 = jsdisp_propput_idx(jsthis, k, v2, ei);
 
         if(FAILED(hres2)) {
-            VariantClear(&v2);
+            jsval_release(v2);
             return hres2;
         }
     }
@@ -502,12 +495,12 @@ static HRESULT Array_reverse(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsi
 }
 
 /* ECMA-262 3rd Edition    15.4.4.9 */
-static HRESULT Array_shift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_shift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
     DWORD length = 0, i;
-    VARIANT v, ret;
+    jsval_t v, ret;
     HRESULT hres;
 
     TRACE("\n");
@@ -530,7 +523,7 @@ static HRESULT Array_shift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
 
     hres = jsdisp_get_idx(jsthis, 0, &ret, ei);
     if(hres == DISP_E_UNKNOWNNAME) {
-        V_VT(&ret) = VT_EMPTY;
+        ret = jsval_undefined();
         hres = S_OK;
     }
 
@@ -539,7 +532,7 @@ static HRESULT Array_shift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
         if(hres == DISP_E_UNKNOWNNAME)
             hres = jsdisp_delete_idx(jsthis, i-1);
         else if(SUCCEEDED(hres))
-            hres = jsdisp_propput_idx(jsthis, i-1, &v, ei);
+            hres = jsdisp_propput_idx(jsthis, i-1, v, ei);
     }
 
     if(SUCCEEDED(hres)) {
@@ -548,14 +541,18 @@ static HRESULT Array_shift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
             hres = set_length(jsthis, ei, length-1);
     }
 
-    if(SUCCEEDED(hres) && r)
-        hres = variant_to_jsval(&ret, r);
-    VariantClear(&ret);
+    if(FAILED(hres))
+        return hres;
+
+    if(r)
+        *r = ret;
+    else
+        jsval_release(ret);
     return hres;
 }
 
 /* ECMA-262 3rd Edition    15.4.4.10 */
-static HRESULT Array_slice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_slice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *arr, *jsthis;
@@ -570,7 +567,7 @@ static HRESULT Array_slice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
         return hres;
 
     if(argc) {
-        hres = to_number(ctx, argv, ei, &range);
+        hres = to_number_jsval(ctx, argv[0], ei, &range);
         if(FAILED(hres))
             return hres;
 
@@ -583,7 +580,7 @@ static HRESULT Array_slice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
     else start = 0;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &range);
+        hres = to_number_jsval(ctx, argv[1], ei, &range);
         if(FAILED(hres))
             return hres;
 
@@ -600,15 +597,15 @@ static HRESULT Array_slice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
         return hres;
 
     for(idx=start; idx<end; idx++) {
-        VARIANT v;
+        jsval_t v;
 
         hres = jsdisp_get_idx(jsthis, idx, &v, ei);
         if(hres == DISP_E_UNKNOWNNAME)
             continue;
 
         if(SUCCEEDED(hres)) {
-            hres = jsdisp_propput_idx(arr, idx-start, &v, ei);
-            VariantClear(&v);
+            hres = jsdisp_propput_idx(arr, idx-start, v, ei);
+            jsval_release(v);
         }
 
         if(FAILED(hres)) {
@@ -625,17 +622,14 @@ static HRESULT Array_slice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsign
     return S_OK;
 }
 
-static HRESULT sort_cmp(script_ctx_t *ctx, jsdisp_t *cmp_func, VARIANT *v1, VARIANT *v2, jsexcept_t *ei, INT *cmp)
+static HRESULT sort_cmp(script_ctx_t *ctx, jsdisp_t *cmp_func, jsval_t v1, jsval_t v2, jsexcept_t *ei, INT *cmp)
 {
     HRESULT hres;
 
     if(cmp_func) {
-        VARIANTARG args[2];
-        double n;
+        jsval_t args[2] = {v1, v2};
         jsval_t res;
-
-        args[0] = *v1;
-        args[1] = *v2;
+        double n;
 
         hres = jsdisp_call_value(cmp_func, NULL, DISPATCH_METHOD, 2, args, &res, ei);
         if(FAILED(hres))
@@ -649,12 +643,12 @@ static HRESULT sort_cmp(script_ctx_t *ctx, jsdisp_t *cmp_func, VARIANT *v1, VARI
         if(n == 0)
             *cmp = 0;
         *cmp = n > 0.0 ? 1 : -1;
-    }else if(V_VT(v1) == VT_EMPTY) {
-        *cmp = V_VT(v2) == VT_EMPTY ? 0 : 1;
-    }else if(V_VT(v2) == VT_EMPTY) {
+    }else if(is_undefined(v1)) {
+        *cmp = is_undefined(v2) ? 0 : 1;
+    }else if(is_undefined(v2)) {
         *cmp = -1;
-    }else if(is_num_vt(V_VT(v1)) && is_num_vt(V_VT(v2))) {
-        DOUBLE d = num_val(v1)-num_val(v2);
+    }else if(is_number(v1) && is_number(v2)) {
+        double d = get_number(v1)-get_number(v2);
         if(d > 0.0)
             *cmp = 1;
         else
@@ -662,11 +656,11 @@ static HRESULT sort_cmp(script_ctx_t *ctx, jsdisp_t *cmp_func, VARIANT *v1, VARI
     }else {
         BSTR x, y;
 
-        hres = to_string(ctx, v1, ei, &x);
+        hres = to_string_jsval(ctx, v1, ei, &x);
         if(FAILED(hres))
             return hres;
 
-        hres = to_string(ctx, v2, ei, &y);
+        hres = to_string_jsval(ctx, v2, ei, &y);
         if(SUCCEEDED(hres)) {
             *cmp = strcmpW(x, y);
             SysFreeString(y);
@@ -680,11 +674,11 @@ static HRESULT sort_cmp(script_ctx_t *ctx, jsdisp_t *cmp_func, VARIANT *v1, VARI
 }
 
 /* ECMA-262 3rd Edition    15.4.4.11 */
-static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis, *cmp_func = NULL;
-    VARIANT *vtab, **sorttab = NULL;
+    jsval_t *vtab, **sorttab = NULL;
     DWORD length;
     DWORD i;
     HRESULT hres = S_OK;
@@ -701,13 +695,12 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
     }
 
     if(argc == 1) {
-        if(V_VT(argv) != VT_DISPATCH) {
+        if(!is_object_instance(argv[0])) {
             WARN("arg is not dispatch\n");
             return E_FAIL;
         }
 
-
-        cmp_func = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv));
+        cmp_func = iface_to_jsdisp((IUnknown*)get_object(argv[0]));
         if(!cmp_func || !is_class(cmp_func, JSCLASS_FUNCTION)) {
             WARN("cmp_func is not a function\n");
             if(cmp_func)
@@ -724,12 +717,12 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
         return S_OK;
     }
 
-    vtab = heap_alloc_zero(length * sizeof(VARIANT));
+    vtab = heap_alloc_zero(length * sizeof(*vtab));
     if(vtab) {
         for(i=0; i<length; i++) {
             hres = jsdisp_get_idx(jsthis, i, vtab+i, ei);
             if(hres == DISP_E_UNKNOWNNAME) {
-                V_VT(vtab+i) = VT_EMPTY;
+                vtab[i] = jsval_undefined();
                 hres = S_OK;
             } else if(FAILED(hres)) {
                 WARN("Could not get elem %d: %08x\n", i, hres);
@@ -741,14 +734,14 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
     }
 
     if(SUCCEEDED(hres)) {
-        sorttab = heap_alloc(length*2*sizeof(VARIANT*));
+        sorttab = heap_alloc(length*2*sizeof(*sorttab));
         if(!sorttab)
             hres = E_OUTOFMEMORY;
     }
 
     /* merge-sort */
     if(SUCCEEDED(hres)) {
-        VARIANT *tmpv, **tmpbuf;
+        jsval_t *tmpv, **tmpbuf;
         INT cmp;
 
         tmpbuf = sorttab + length;
@@ -756,7 +749,7 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
             sorttab[i] = vtab+i;
 
         for(i=0; i < length/2; i++) {
-            hres = sort_cmp(ctx, cmp_func, sorttab[2*i+1], sorttab[2*i], ei, &cmp);
+            hres = sort_cmp(ctx, cmp_func, *sorttab[2*i+1], *sorttab[2*i], ei, &cmp);
             if(FAILED(hres))
                 break;
 
@@ -778,10 +771,10 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
                     else
                         bend = length - (i+k);
 
-                    memcpy(tmpbuf, sorttab+i, k*sizeof(VARIANT*));
+                    memcpy(tmpbuf, sorttab+i, k*sizeof(jsval_t*));
 
                     while(a < k && b < bend) {
-                        hres = sort_cmp(ctx, cmp_func, tmpbuf[a], sorttab[i+k+b], ei, &cmp);
+                        hres = sort_cmp(ctx, cmp_func, *tmpbuf[a], *sorttab[i+k+b], ei, &cmp);
                         if(FAILED(hres))
                             break;
 
@@ -798,7 +791,7 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
                         break;
 
                     if(a < k)
-                        memcpy(sorttab+i+a+b, tmpbuf+a, (k-a)*sizeof(VARIANT*));
+                        memcpy(sorttab+i+a+b, tmpbuf+a, (k-a)*sizeof(jsval_t*));
                 }
 
                 if(FAILED(hres))
@@ -807,12 +800,12 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
         }
 
         for(i=0; SUCCEEDED(hres) && i < length; i++)
-            hres = jsdisp_propput_idx(jsthis, i, sorttab[i], ei);
+            hres = jsdisp_propput_idx(jsthis, i, *sorttab[i], ei);
     }
 
     if(vtab) {
         for(i=0; i < length; i++)
-            VariantClear(vtab+i);
+            jsval_release(vtab[i]);
         heap_free(vtab);
     }
     heap_free(sorttab);
@@ -828,12 +821,12 @@ static HRESULT Array_sort(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigne
 }
 
 /* ECMA-262 3rd Edition    15.4.4.12 */
-static HRESULT Array_splice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_splice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DWORD length, start=0, delete_cnt=0, i, add_args = 0;
     jsdisp_t *ret_array = NULL, *jsthis;
-    VARIANT v;
+    jsval_t val;
     double d;
     int n;
     HRESULT hres = S_OK;
@@ -845,7 +838,7 @@ static HRESULT Array_splice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsig
         return hres;
 
     if(argc) {
-        hres = to_integer(ctx, argv, ei, &d);
+        hres = to_integer(ctx, argv[0], ei, &d);
         if(FAILED(hres))
             return hres;
 
@@ -860,7 +853,7 @@ static HRESULT Array_splice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsig
     }
 
     if(argc >= 2) {
-        hres = to_integer(ctx, argv+1, ei, &d);
+        hres = to_integer(ctx, argv[1], ei, &d);
         if(FAILED(hres))
             return hres;
 
@@ -880,47 +873,49 @@ static HRESULT Array_splice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsig
             return hres;
 
         for(i=0; SUCCEEDED(hres) && i < delete_cnt; i++) {
-            hres = jsdisp_get_idx(jsthis, start+i, &v, ei);
-            if(hres == DISP_E_UNKNOWNNAME)
+            hres = jsdisp_get_idx(jsthis, start+i, &val, ei);
+            if(hres == DISP_E_UNKNOWNNAME) {
                 hres = S_OK;
-            else if(SUCCEEDED(hres))
-                hres = jsdisp_propput_idx(ret_array, i, &v, ei);
+            }else if(SUCCEEDED(hres)) {
+                hres = jsdisp_propput_idx(ret_array, i, val, ei);
+                jsval_release(val);
+            }
         }
 
-        if(SUCCEEDED(hres)) {
-            num_set_int(&v, delete_cnt);
-            hres = jsdisp_propput_name(ret_array, lengthW, &v, ei);
-        }
+        if(SUCCEEDED(hres))
+            hres = jsdisp_propput_name(ret_array, lengthW, jsval_number(delete_cnt), ei);
     }
 
     if(add_args < delete_cnt) {
         for(i = start; SUCCEEDED(hres) && i < length-delete_cnt; i++) {
-            hres = jsdisp_get_idx(jsthis, i+delete_cnt, &v, ei);
-            if(hres == DISP_E_UNKNOWNNAME)
+            hres = jsdisp_get_idx(jsthis, i+delete_cnt, &val, ei);
+            if(hres == DISP_E_UNKNOWNNAME) {
                 hres = jsdisp_delete_idx(jsthis, i+add_args);
-            else if(SUCCEEDED(hres))
-                hres = jsdisp_propput_idx(jsthis, i+add_args, &v, ei);
+            }else if(SUCCEEDED(hres)) {
+                hres = jsdisp_propput_idx(jsthis, i+add_args, val, ei);
+                jsval_release(val);
+            }
         }
 
         for(i=length; SUCCEEDED(hres) && i != length-delete_cnt+add_args; i--)
             hres = jsdisp_delete_idx(jsthis, i-1);
     }else if(add_args > delete_cnt) {
         for(i=length-delete_cnt; SUCCEEDED(hres) && i != start; i--) {
-            hres = jsdisp_get_idx(jsthis, i+delete_cnt-1, &v, ei);
-            if(hres == DISP_E_UNKNOWNNAME)
+            hres = jsdisp_get_idx(jsthis, i+delete_cnt-1, &val, ei);
+            if(hres == DISP_E_UNKNOWNNAME) {
                 hres = jsdisp_delete_idx(jsthis, i+add_args-1);
-            else if(SUCCEEDED(hres))
-                hres = jsdisp_propput_idx(jsthis, i+add_args-1, &v, ei);
+            }else if(SUCCEEDED(hres)) {
+                hres = jsdisp_propput_idx(jsthis, i+add_args-1, val, ei);
+                jsval_release(val);
+            }
         }
     }
 
     for(i=0; SUCCEEDED(hres) && i < add_args; i++)
-        hres = jsdisp_propput_idx(jsthis, start+i, argv+i+2, ei);
+        hres = jsdisp_propput_idx(jsthis, start+i, argv[i+2], ei);
 
-    if(SUCCEEDED(hres)) {
-        num_set_int(&v, length-delete_cnt+add_args);
-        hres = jsdisp_propput_name(jsthis, lengthW, &v, ei);
-    }
+    if(SUCCEEDED(hres))
+        hres = jsdisp_propput_name(jsthis, lengthW, jsval_number(length-delete_cnt+add_args), ei);
 
     if(FAILED(hres)) {
         if(ret_array)
@@ -934,7 +929,7 @@ static HRESULT Array_splice(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsig
 }
 
 /* ECMA-262 3rd Edition    15.4.4.2 */
-static HRESULT Array_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     ArrayInstance *array;
@@ -948,7 +943,7 @@ static HRESULT Array_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return array_join(ctx, &array->dispex, array->length, default_separatorW, r, ei);
 }
 
-static HRESULT Array_toLocaleString(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_toLocaleString(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
@@ -956,13 +951,13 @@ static HRESULT Array_toLocaleString(script_ctx_t *ctx, vdisp_t *vthis, WORD flag
 }
 
 /* ECMA-262 3rd Edition    15.4.4.13 */
-static HRESULT Array_unshift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_unshift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
     WCHAR buf[14], *buf_end, *str;
     DWORD i, length;
-    VARIANT var;
+    jsval_t val;
     DISPID id;
     HRESULT hres;
 
@@ -982,12 +977,12 @@ static HRESULT Array_unshift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsi
 
             hres = jsdisp_get_id(jsthis, str, 0, &id);
             if(SUCCEEDED(hres)) {
-                hres = jsdisp_propget(jsthis, id, &var, ei);
+                hres = jsdisp_propget(jsthis, id, &val, ei);
                 if(FAILED(hres))
                     return hres;
 
-                hres = jsdisp_propput_idx(jsthis, i+argc, &var, ei);
-                VariantClear(&var);
+                hres = jsdisp_propput_idx(jsthis, i+argc, val, ei);
+                jsval_release(val);
             }else if(hres == DISP_E_UNKNOWNNAME) {
                 hres = IDispatchEx_DeleteMemberByDispID(vthis->u.dispex, id);
             }
@@ -998,7 +993,7 @@ static HRESULT Array_unshift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsi
     }
 
     for(i=0; i<argc; i++) {
-        hres = jsdisp_propput_idx(jsthis, i, argv+i, ei);
+        hres = jsdisp_propput_idx(jsthis, i, argv[i], ei);
         if(FAILED(hres))
             return hres;
     }
@@ -1015,7 +1010,7 @@ static HRESULT Array_unshift(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsi
     return S_OK;
 }
 
-static HRESULT Array_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Array_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -1097,7 +1092,7 @@ static const builtin_info_t ArrayInst_info = {
     Array_on_put
 };
 
-static HRESULT ArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT ArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *obj;
@@ -1109,11 +1104,13 @@ static HRESULT ArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
     switch(flags) {
     case DISPATCH_METHOD:
     case DISPATCH_CONSTRUCT: {
-        if(argc == 1 && V_VT(argv) == VT_I4) {
-            if(V_I4(argv) < 0)
+        if(argc == 1 && is_number(argv[0])) {
+            double n = get_number(argv[0]);
+
+            if(n < 0 || !is_int32(n))
                 return throw_range_error(ctx, ei, JS_E_INVALID_LENGTH, NULL);
 
-            hres = create_array(ctx, V_I4(argv), &obj);
+            hres = create_array(ctx, n, &obj);
             if(FAILED(hres))
                 return hres;
 
@@ -1126,7 +1123,7 @@ static HRESULT ArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
             return hres;
 
         for(i=0; i < argc; i++) {
-            hres = jsdisp_propput_idx(obj, i, argv+i, ei);
+            hres = jsdisp_propput_idx(obj, i, argv[i], ei);
             if(FAILED(hres))
                 break;
         }
diff --git a/dlls/jscript/bool.c b/dlls/jscript/bool.c
index aa47640c072..f8b4f849e56 100644
--- a/dlls/jscript/bool.c
+++ b/dlls/jscript/bool.c
@@ -38,7 +38,7 @@ static inline BoolInstance *bool_this(vdisp_t *jsthis)
 }
 
 /* ECMA-262 3rd Edition    15.6.4.2 */
-static HRESULT Bool_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Bool_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BoolInstance *bool;
@@ -67,7 +67,7 @@ static HRESULT Bool_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.6.4.3 */
-static HRESULT Bool_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Bool_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BoolInstance *bool;
@@ -82,7 +82,7 @@ static HRESULT Bool_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     return S_OK;
 }
 
-static HRESULT Bool_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Bool_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -121,14 +121,14 @@ static const builtin_info_t BoolInst_info = {
     NULL
 };
 
-static HRESULT BoolConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT BoolConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
+    BOOL value = FALSE;
     HRESULT hres;
-    VARIANT_BOOL value = VARIANT_FALSE;
 
     if(argc) {
-        hres = to_boolean(argv, &value);
+        hres = to_boolean_jsval(argv[0], &value);
         if(FAILED(hres))
             return hres;
     }
diff --git a/dlls/jscript/date.c b/dlls/jscript/date.c
index 926e8fce2ac..ae83444c071 100644
--- a/dlls/jscript/date.c
+++ b/dlls/jscript/date.c
@@ -601,7 +601,7 @@ static HRESULT dateobj_to_string(DateInstance *date, jsval_t *r)
     return date_to_string(time, TRUE, offset, r);
 }
 
-static HRESULT Date_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -615,7 +615,7 @@ static HRESULT Date_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.9.1.5 */
-static HRESULT Date_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR NaNW[] = { 'N','a','N',0 };
@@ -659,7 +659,7 @@ static HRESULT Date_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
     return S_OK;
 }
 
-static HRESULT Date_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -777,14 +777,14 @@ static inline HRESULT create_utc_string(script_ctx_t *ctx, vdisp_t *jsthis,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.42 */
-static HRESULT Date_toUTCString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toUTCString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return create_utc_string(ctx, jsthis, r, ei);
 }
 
-static HRESULT Date_toGMTString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toGMTString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -888,7 +888,7 @@ static HRESULT dateobj_to_date_string(DateInstance *date, jsval_t *r)
     return S_OK;
 }
 
-static HRESULT Date_toDateString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toDateString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -900,7 +900,7 @@ static HRESULT Date_toDateString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.4 */
-static HRESULT Date_toTimeString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toTimeString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR NaNW[] = { 'N','a','N',0 };
@@ -958,7 +958,7 @@ static HRESULT Date_toTimeString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.6 */
-static HRESULT Date_toLocaleDateString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toLocaleDateString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR NaNW[] = { 'N','a','N',0 };
@@ -1000,7 +1000,7 @@ static HRESULT Date_toLocaleDateString(script_ctx_t *ctx, vdisp_t *jsthis, WORD
 }
 
 /* ECMA-262 3rd Edition    15.9.5.7 */
-static HRESULT Date_toLocaleTimeString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_toLocaleTimeString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR NaNW[] = { 'N','a','N',0 };
@@ -1042,7 +1042,7 @@ static HRESULT Date_toLocaleTimeString(script_ctx_t *ctx, vdisp_t *jsthis, WORD
 }
 
 /* ECMA-262 3rd Edition    15.9.5.9 */
-static HRESULT Date_getTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1058,7 +1058,7 @@ static HRESULT Date_getTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 }
 
 /* ECMA-262 3rd Edition    15.9.5.10 */
-static HRESULT Date_getFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1077,7 +1077,7 @@ static HRESULT Date_getFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.11 */
-static HRESULT Date_getUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1093,7 +1093,7 @@ static HRESULT Date_getUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
 }
 
 /* ECMA-262 3rd Edition    15.9.5.12 */
-static HRESULT Date_getMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1109,7 +1109,7 @@ static HRESULT Date_getMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.9.5.13 */
-static HRESULT Date_getUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1125,7 +1125,7 @@ static HRESULT Date_getUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.14 */
-static HRESULT Date_getDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1141,7 +1141,7 @@ static HRESULT Date_getDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 }
 
 /* ECMA-262 3rd Edition    15.9.5.15 */
-static HRESULT Date_getUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1157,7 +1157,7 @@ static HRESULT Date_getUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.9.5.16 */
-static HRESULT Date_getDay(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getDay(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1173,7 +1173,7 @@ static HRESULT Date_getDay(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
 }
 
 /* ECMA-262 3rd Edition    15.9.5.17 */
-static HRESULT Date_getUTCDay(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCDay(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1189,7 +1189,7 @@ static HRESULT Date_getUTCDay(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
 }
 
 /* ECMA-262 3rd Edition    15.9.5.18 */
-static HRESULT Date_getHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1205,7 +1205,7 @@ static HRESULT Date_getHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.9.5.19 */
-static HRESULT Date_getUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1221,7 +1221,7 @@ static HRESULT Date_getUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.20 */
-static HRESULT Date_getMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1237,7 +1237,7 @@ static HRESULT Date_getMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.9.5.21 */
-static HRESULT Date_getUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1253,7 +1253,7 @@ static HRESULT Date_getUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
 }
 
 /* ECMA-262 3rd Edition    15.9.5.22 */
-static HRESULT Date_getSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1269,7 +1269,7 @@ static HRESULT Date_getSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.9.5.23 */
-static HRESULT Date_getUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1285,7 +1285,7 @@ static HRESULT Date_getUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
 }
 
 /* ECMA-262 3rd Edition    15.9.5.24 */
-static HRESULT Date_getMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1301,7 +1301,7 @@ static HRESULT Date_getMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
 }
 
 /* ECMA-262 3rd Edition    15.9.5.25 */
-static HRESULT Date_getUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1317,7 +1317,7 @@ static HRESULT Date_getUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD
 }
 
 /* ECMA-262 3rd Edition    15.9.5.26 */
-static HRESULT Date_getTimezoneOffset(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getTimezoneOffset(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1333,7 +1333,7 @@ static HRESULT Date_getTimezoneOffset(script_ctx_t *ctx, vdisp_t *jsthis, WORD f
 }
 
 /* ECMA-262 3rd Edition    15.9.5.27 */
-static HRESULT Date_setTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double n;
@@ -1348,7 +1348,7 @@ static HRESULT Date_setTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     if(!argc)
         return throw_type_error(ctx, ei, JS_E_MISSING_ARG, NULL);
 
-    hres = to_number(ctx, argv, ei, &n);
+    hres = to_number_jsval(ctx, argv[0], ei, &n);
     if(FAILED(hres))
         return hres;
 
@@ -1360,7 +1360,7 @@ static HRESULT Date_setTime(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 }
 
 /* ECMA-262 3rd Edition    15.9.5.28 */
-static HRESULT Date_setMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1375,7 +1375,7 @@ static HRESULT Date_setMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
     if(!argc)
         return throw_type_error(ctx, ei, JS_E_MISSING_ARG, NULL);
 
-    hres = to_number(ctx, argv, ei, &n);
+    hres = to_number_jsval(ctx, argv[0], ei, &n);
     if(FAILED(hres))
         return hres;
 
@@ -1390,7 +1390,7 @@ static HRESULT Date_setMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
 }
 
 /* ECMA-262 3rd Edition    15.9.5.29 */
-static HRESULT Date_setUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1405,7 +1405,7 @@ static HRESULT Date_setUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD
     if(!argc)
         return throw_type_error(ctx, ei, JS_E_MISSING_ARG, NULL);
 
-    hres = to_number(ctx, argv, ei, &n);
+    hres = to_number_jsval(ctx, argv[0], ei, &n);
     if(FAILED(hres))
         return hres;
 
@@ -1420,7 +1420,7 @@ static HRESULT Date_setUTCMilliseconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD
 }
 
 /* ECMA-262 3rd Edition    15.9.5.30 */
-static HRESULT Date_setSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1437,12 +1437,12 @@ static HRESULT Date_setSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 
     t = local_time(date->time, date);
 
-    hres = to_number(ctx, argv, ei, &sec);
+    hres = to_number_jsval(ctx, argv[0], ei, &sec);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &ms);
+        hres = to_number_jsval(ctx, argv[1], ei, &ms);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1459,7 +1459,7 @@ static HRESULT Date_setSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.9.5.31 */
-static HRESULT Date_setUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1476,12 +1476,12 @@ static HRESULT Date_setUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
 
     t = date->time;
 
-    hres = to_number(ctx, argv, ei, &sec);
+    hres = to_number_jsval(ctx, argv[0], ei, &sec);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &ms);
+        hres = to_number_jsval(ctx, argv[1], ei, &ms);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1498,7 +1498,7 @@ static HRESULT Date_setUTCSeconds(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
 }
 
 /* ECMA-262 3rd Edition    15.9.5.33 */
-static HRESULT Date_setMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1515,12 +1515,12 @@ static HRESULT Date_setMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 
     t = local_time(date->time, date);
 
-    hres = to_number(ctx, argv, ei, &min);
+    hres = to_number_jsval(ctx, argv[0], ei, &min);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &sec);
+        hres = to_number_jsval(ctx, argv[1], ei, &sec);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1528,7 +1528,7 @@ static HRESULT Date_setMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     }
 
     if(argc > 2) {
-        hres = to_number(ctx, argv+2, ei, &ms);
+        hres = to_number_jsval(ctx, argv[2], ei, &ms);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1545,7 +1545,7 @@ static HRESULT Date_setMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.9.5.34 */
-static HRESULT Date_setUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1562,12 +1562,12 @@ static HRESULT Date_setUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
 
     t = date->time;
 
-    hres = to_number(ctx, argv, ei, &min);
+    hres = to_number_jsval(ctx, argv[0], ei, &min);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &sec);
+        hres = to_number_jsval(ctx, argv[1], ei, &sec);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1575,7 +1575,7 @@ static HRESULT Date_setUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     }
 
     if(argc > 2) {
-        hres = to_number(ctx, argv+2, ei, &ms);
+        hres = to_number_jsval(ctx, argv[2], ei, &ms);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1592,7 +1592,7 @@ static HRESULT Date_setUTCMinutes(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
 }
 
 /* ECMA-262 3rd Edition    15.9.5.35 */
-static HRESULT Date_setHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1609,12 +1609,12 @@ static HRESULT Date_setHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 
     t = local_time(date->time, date);
 
-    hres = to_number(ctx, argv, ei, &hour);
+    hres = to_number_jsval(ctx, argv[0], ei, &hour);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &min);
+        hres = to_number_jsval(ctx, argv[1], ei, &min);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1622,7 +1622,7 @@ static HRESULT Date_setHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     }
 
     if(argc > 2) {
-        hres = to_number(ctx, argv+2, ei, &sec);
+        hres = to_number_jsval(ctx, argv[2], ei, &sec);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1630,7 +1630,7 @@ static HRESULT Date_setHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     }
 
     if(argc > 3) {
-        hres = to_number(ctx, argv+3, ei, &ms);
+        hres = to_number_jsval(ctx, argv[3], ei, &ms);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1646,7 +1646,7 @@ static HRESULT Date_setHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.9.5.36 */
-static HRESULT Date_setUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1663,12 +1663,12 @@ static HRESULT Date_setUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 
     t = date->time;
 
-    hres = to_number(ctx, argv, ei, &hour);
+    hres = to_number_jsval(ctx, argv[0], ei, &hour);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &min);
+        hres = to_number_jsval(ctx, argv[1], ei, &min);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1676,7 +1676,7 @@ static HRESULT Date_setUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     }
 
     if(argc > 2) {
-        hres = to_number(ctx, argv+2, ei, &sec);
+        hres = to_number_jsval(ctx, argv[2], ei, &sec);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1684,7 +1684,7 @@ static HRESULT Date_setUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     }
 
     if(argc > 3) {
-        hres = to_number(ctx, argv+3, ei, &ms);
+        hres = to_number_jsval(ctx, argv[3], ei, &ms);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1700,7 +1700,7 @@ static HRESULT Date_setUTCHours(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.36 */
-static HRESULT Date_setDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1715,7 +1715,7 @@ static HRESULT Date_setDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     if(!argc)
         return throw_type_error(ctx, ei, JS_E_MISSING_ARG, NULL);
 
-    hres = to_number(ctx, argv, ei, &n);
+    hres = to_number_jsval(ctx, argv[0], ei, &n);
     if(FAILED(hres))
         return hres;
 
@@ -1729,7 +1729,7 @@ static HRESULT Date_setDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 }
 
 /* ECMA-262 3rd Edition    15.9.5.37 */
-static HRESULT Date_setUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1744,7 +1744,7 @@ static HRESULT Date_setUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     if(!argc)
         return throw_type_error(ctx, ei, JS_E_MISSING_ARG, NULL);
 
-    hres = to_number(ctx, argv, ei, &n);
+    hres = to_number_jsval(ctx, argv[0], ei, &n);
     if(FAILED(hres))
         return hres;
 
@@ -1758,7 +1758,7 @@ static HRESULT Date_setUTCDate(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.9.5.38 */
-static HRESULT Date_setMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1775,12 +1775,12 @@ static HRESULT Date_setMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 
     t = local_time(date->time, date);
 
-    hres = to_number(ctx, argv, ei, &month);
+    hres = to_number_jsval(ctx, argv[0], ei, &month);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &ddate);
+        hres = to_number_jsval(ctx, argv[1], ei, &ddate);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1797,7 +1797,7 @@ static HRESULT Date_setMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.9.5.39 */
-static HRESULT Date_setUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1814,12 +1814,12 @@ static HRESULT Date_setUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 
     t = date->time;
 
-    hres = to_number(ctx, argv, ei, &month);
+    hres = to_number_jsval(ctx, argv[0], ei, &month);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &ddate);
+        hres = to_number_jsval(ctx, argv[1], ei, &ddate);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1836,7 +1836,7 @@ static HRESULT Date_setUTCMonth(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.40 */
-static HRESULT Date_setFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1853,12 +1853,12 @@ static HRESULT Date_setFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 
     t = local_time(date->time, date);
 
-    hres = to_number(ctx, argv, ei, &year);
+    hres = to_number_jsval(ctx, argv[0], ei, &year);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &month);
+        hres = to_number_jsval(ctx, argv[1], ei, &month);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1866,7 +1866,7 @@ static HRESULT Date_setFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     }
 
     if(argc > 2) {
-        hres = to_number(ctx, argv+2, ei, &ddate);
+        hres = to_number_jsval(ctx, argv[2], ei, &ddate);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1882,7 +1882,7 @@ static HRESULT Date_setFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.9.5.41 */
-static HRESULT Date_setUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1899,12 +1899,12 @@ static HRESULT Date_setUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
 
     t = date->time;
 
-    hres = to_number(ctx, argv, ei, &year);
+    hres = to_number_jsval(ctx, argv[0], ei, &year);
     if(FAILED(hres))
         return hres;
 
     if(argc > 1) {
-        hres = to_number(ctx, argv+1, ei, &month);
+        hres = to_number_jsval(ctx, argv[1], ei, &month);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1912,7 +1912,7 @@ static HRESULT Date_setUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
     }
 
     if(argc > 2) {
-        hres = to_number(ctx, argv+2, ei, &ddate);
+        hres = to_number_jsval(ctx, argv[2], ei, &ddate);
         if(FAILED(hres))
             return hres;
     }else {
@@ -1928,7 +1928,7 @@ static HRESULT Date_setUTCFullYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
 }
 
 /* ECMA-262 3rd Edition    B2.4 */
-static HRESULT Date_getYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_getYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1953,7 +1953,7 @@ static HRESULT Date_getYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 }
 
 /* ECMA-262 3rd Edition    B2.5 */
-static HRESULT Date_setYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_setYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DateInstance *date;
@@ -1970,7 +1970,7 @@ static HRESULT Date_setYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
 
     t = local_time(date->time, date);
 
-    hres = to_number(ctx, argv, ei, &year);
+    hres = to_number_jsval(ctx, argv[0], ei, &year);
     if(FAILED(hres))
         return hres;
 
@@ -1992,7 +1992,7 @@ static HRESULT Date_setYear(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     return S_OK;
 }
 
-static HRESULT Date_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Date_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -2365,7 +2365,7 @@ static inline HRESULT date_parse(BSTR input, double *ret) {
     return S_OK;
 }
 
-static HRESULT DateConstr_parse(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT DateConstr_parse(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR parse_str;
@@ -2380,7 +2380,7 @@ static HRESULT DateConstr_parse(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &parse_str);
+    hres = to_string_jsval(ctx, argv[0], ei, &parse_str);
     if(FAILED(hres))
         return hres;
 
@@ -2393,7 +2393,7 @@ static HRESULT DateConstr_parse(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return S_OK;
 }
 
-static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double *ret, jsexcept_t *ei)
+static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, jsval_t *argv, double *ret, jsexcept_t *ei)
 {
     double year, month, vdate, hours, minutes, seconds, ms;
     HRESULT hres;
@@ -2401,7 +2401,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     TRACE("\n");
 
     if(argc) {
-        hres = to_number(ctx, argv, ei, &year);
+        hres = to_number_jsval(ctx, argv[0], ei, &year);
         if(FAILED(hres))
             return hres;
         if(0 <= year && year <= 99)
@@ -2411,7 +2411,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     }
 
     if(argc>1) {
-        hres = to_number(ctx, argv+1, ei, &month);
+        hres = to_number_jsval(ctx, argv[1], ei, &month);
         if(FAILED(hres))
             return hres;
     }else {
@@ -2419,7 +2419,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     }
 
     if(argc>2) {
-        hres = to_number(ctx, argv+2, ei, &vdate);
+        hres = to_number_jsval(ctx, argv[2], ei, &vdate);
         if(FAILED(hres))
             return hres;
     }else {
@@ -2427,7 +2427,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     }
 
     if(argc>3) {
-        hres = to_number(ctx, argv+3, ei, &hours);
+        hres = to_number_jsval(ctx, argv[3], ei, &hours);
         if(FAILED(hres))
             return hres;
     }else {
@@ -2435,7 +2435,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     }
 
     if(argc>4) {
-        hres = to_number(ctx, argv+4, ei, &minutes);
+        hres = to_number_jsval(ctx, argv[4], ei, &minutes);
         if(FAILED(hres))
             return hres;
     }else {
@@ -2443,7 +2443,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     }
 
     if(argc>5) {
-        hres = to_number(ctx, argv+5, ei, &seconds);
+        hres = to_number_jsval(ctx, argv[5], ei, &seconds);
         if(FAILED(hres))
             return hres;
     }else {
@@ -2451,7 +2451,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     }
 
     if(argc>6) {
-        hres = to_number(ctx, argv+6, ei, &ms);
+        hres = to_number_jsval(ctx, argv[6], ei, &ms);
         if(FAILED(hres))
             return hres;
     } else {
@@ -2463,7 +2463,7 @@ static HRESULT date_utc(script_ctx_t *ctx, unsigned argc, VARIANT *argv, double
     return S_OK;
 }
 
-static HRESULT DateConstr_UTC(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT DateConstr_UTC(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double n;
@@ -2477,7 +2477,7 @@ static HRESULT DateConstr_UTC(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return hres;
 }
 
-static HRESULT DateConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT DateConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *date;
@@ -2505,10 +2505,14 @@ static HRESULT DateConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 
         /* ECMA-262 3rd Edition    15.9.3.2 */
         case 1: {
-            VARIANT prim;
+            VARIANT prim,var;
             double n;
 
-            hres = to_primitive(ctx, argv, ei, &prim, NO_HINT);
+            hres = jsval_to_variant(argv[0], &var);
+            if(SUCCEEDED(hres)) {
+                hres = to_primitive(ctx, &var, ei, &prim, NO_HINT);
+                VariantClear(&var);
+            }
             if(FAILED(hres))
                 return hres;
 
diff --git a/dlls/jscript/dispex.c b/dlls/jscript/dispex.c
index e0912fbb0d7..e3680c5abb5 100644
--- a/dlls/jscript/dispex.c
+++ b/dlls/jscript/dispex.c
@@ -309,17 +309,17 @@ static IDispatch *get_this(DISPPARAMS *dp)
     return NULL;
 }
 
-static HRESULT convert_params(const DISPPARAMS *dp, VARIANT *buf, unsigned *argc, VARIANT **ret)
+static HRESULT convert_params(const DISPPARAMS *dp, jsval_t *buf, unsigned *argc, jsval_t **ret)
 {
-    const VARIANT *s;
-    VARIANT *argv;
+    jsval_t *argv;
     unsigned cnt;
     unsigned i;
+    HRESULT hres;
 
     cnt = dp->cArgs - dp->cNamedArgs;
 
     if(cnt > 6) {
-        argv = heap_alloc(cnt * sizeof(VARIANT));
+        argv = heap_alloc(cnt * sizeof(*argv));
         if(!argv)
             return E_OUTOFMEMORY;
     }else {
@@ -327,18 +327,13 @@ static HRESULT convert_params(const DISPPARAMS *dp, VARIANT *buf, unsigned *argc
     }
 
     for(i = 0; i < cnt; i++) {
-        s = dp->rgvarg+dp->cArgs-i-1;
-        switch(V_VT(s)) {
-        case VT_I2:
-            V_VT(argv+i) = VT_I4;
-            V_I4(argv+i) = V_I2(s);
-            break;
-        case VT_INT:
-            V_VT(argv+i) = VT_I4;
-            V_I4(argv+i) = V_INT(s);
-            break;
-        default:
-            argv[i] = *s;
+        hres = variant_to_jsval(dp->rgvarg+dp->cArgs-i-1, argv+i);
+        if(FAILED(hres)) {
+            while(i--)
+                jsval_release(argv[i]);
+            if(argv != buf)
+                heap_free(argv);
+            return hres;
         }
     }
 
@@ -348,7 +343,7 @@ static HRESULT convert_params(const DISPPARAMS *dp, VARIANT *buf, unsigned *argc
 }
 
 static HRESULT invoke_prop_func(jsdisp_t *This, IDispatch *jsthis, dispex_prop_t *prop, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei, IServiceProvider *caller)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei, IServiceProvider *caller)
 {
     HRESULT hres;
 
@@ -395,7 +390,7 @@ static HRESULT invoke_prop_func(jsdisp_t *This, IDispatch *jsthis, dispex_prop_t
 }
 
 static HRESULT prop_get(jsdisp_t *This, dispex_prop_t *prop, DISPPARAMS *dp,
-        VARIANT *retv, jsexcept_t *ei, IServiceProvider *caller)
+        jsval_t *r, jsexcept_t *ei, IServiceProvider *caller)
 {
     HRESULT hres;
 
@@ -410,25 +405,20 @@ static HRESULT prop_get(jsdisp_t *This, dispex_prop_t *prop, DISPPARAMS *dp,
 
             prop->type = PROP_VARIANT;
             var_set_jsdisp(&prop->u.var, obj);
-            hres = VariantCopy(retv, &prop->u.var);
+            hres = variant_to_jsval(&prop->u.var, r);
         }else {
             vdisp_t vthis;
-            jsval_t r;
 
             set_jsdisp(&vthis, This);
-            hres = prop->u.p->invoke(This->ctx, &vthis, DISPATCH_PROPERTYGET, 0, NULL, &r, ei);
+            hres = prop->u.p->invoke(This->ctx, &vthis, DISPATCH_PROPERTYGET, 0, NULL, r, ei);
             vdisp_release(&vthis);
-            if(SUCCEEDED(hres)) {
-                hres = jsval_to_variant(r, retv);
-                jsval_release(r);
-            }
         }
         break;
     case PROP_PROTREF:
-        hres = prop_get(This->prototype, This->prototype->props+prop->u.ref, dp, retv, ei, caller);
+        hres = prop_get(This->prototype, This->prototype->props+prop->u.ref, dp, r, ei, caller);
         break;
     case PROP_VARIANT:
-        hres = VariantCopy(retv, &prop->u.var);
+        hres = variant_to_jsval(&prop->u.var, r);
         break;
     default:
         ERR("type %d\n", prop->type);
@@ -440,11 +430,11 @@ static HRESULT prop_get(jsdisp_t *This, dispex_prop_t *prop, DISPPARAMS *dp,
         return hres;
     }
 
-    TRACE("%s ret %s\n", debugstr_w(prop->name), debugstr_variant(retv));
+    TRACE("%s ret %s\n", debugstr_w(prop->name), debugstr_jsval(*r));
     return hres;
 }
 
-static HRESULT prop_put(jsdisp_t *This, dispex_prop_t *prop, VARIANT *val,
+static HRESULT prop_put(jsdisp_t *This, dispex_prop_t *prop, jsval_t val,
         jsexcept_t *ei, IServiceProvider *caller)
 {
     HRESULT hres;
@@ -458,7 +448,7 @@ static HRESULT prop_put(jsdisp_t *This, dispex_prop_t *prop, VARIANT *val,
             vdisp_t vthis;
 
             set_jsdisp(&vthis, This);
-            hres = prop->u.p->invoke(This->ctx, &vthis, DISPATCH_PROPERTYPUT, 1, val, NULL, ei);
+            hres = prop->u.p->invoke(This->ctx, &vthis, DISPATCH_PROPERTYPUT, 1, &val, NULL, ei);
             vdisp_release(&vthis);
             return hres;
         }
@@ -475,14 +465,14 @@ static HRESULT prop_put(jsdisp_t *This, dispex_prop_t *prop, VARIANT *val,
         return E_FAIL;
     }
 
-    hres = VariantCopy(&prop->u.var, val);
+    hres = jsval_to_variant(val, &prop->u.var);
     if(FAILED(hres))
         return hres;
 
     if(This->builtin_info->on_put)
         This->builtin_info->on_put(This, prop->name);
 
-    TRACE("%s = %s\n", debugstr_w(prop->name), debugstr_variant(val));
+    TRACE("%s = %s\n", debugstr_w(prop->name), debugstr_jsval(val));
     return S_OK;
 }
 
@@ -682,10 +672,8 @@ static HRESULT WINAPI DispatchEx_InvokeEx(IDispatchEx *iface, DISPID id, LCID lc
         /* fall through */
     case DISPATCH_METHOD:
     case DISPATCH_CONSTRUCT: {
-        VARIANT *argv;
+        jsval_t *argv, buf[6], r;
         unsigned argc;
-        jsval_t r;
-        VARIANT buf[6];
 
         hres = convert_params(pdp, buf, &argc, &argv);
         if(FAILED(hres))
@@ -700,10 +688,18 @@ static HRESULT WINAPI DispatchEx_InvokeEx(IDispatchEx *iface, DISPID id, LCID lc
         }
         break;
     }
-    case DISPATCH_PROPERTYGET:
-        hres = prop_get(This, prop, pdp, pvarRes, &jsexcept, pspCaller);
+    case DISPATCH_PROPERTYGET: {
+        jsval_t r;
+
+        hres = prop_get(This, prop, pdp, &r, &jsexcept, pspCaller);
+        if(SUCCEEDED(hres)) {
+            hres = jsval_to_variant(r, pvarRes);
+            jsval_release(r);
+        }
         break;
+    }
     case DISPATCH_PROPERTYPUT: {
+        jsval_t val;
         DWORD i;
 
         for(i=0; i < pdp->cNamedArgs; i++) {
@@ -716,7 +712,12 @@ static HRESULT WINAPI DispatchEx_InvokeEx(IDispatchEx *iface, DISPID id, LCID lc
             return DISP_E_PARAMNOTOPTIONAL;
         }
 
-        hres = prop_put(This, prop, pdp->rgvarg+i, &jsexcept, pspCaller);
+        hres = variant_to_jsval(pdp->rgvarg+i, &val);
+        if(FAILED(hres))
+            return hres;
+
+        hres = prop_put(This, prop, val, &jsexcept, pspCaller);
+        jsval_release(val);
         break;
     }
     default:
@@ -937,19 +938,18 @@ HRESULT init_dispex_from_constr(jsdisp_t *dispex, script_ctx_t *ctx, const built
     hres = find_prop_name_prot(constr, string_hash(prototypeW), prototypeW, &prop);
     if(SUCCEEDED(hres) && prop && prop->type!=PROP_DELETED) {
         jsexcept_t jsexcept;
-        VARIANT var;
+        jsval_t val;
 
-        V_VT(&var) = VT_EMPTY;
         memset(&jsexcept, 0, sizeof(jsexcept));
-        hres = prop_get(constr, prop, NULL, &var, &jsexcept, NULL/*FIXME*/);
+        hres = prop_get(constr, prop, NULL, &val, &jsexcept, NULL/*FIXME*/);
         if(FAILED(hres)) {
             ERR("Could not get prototype\n");
             return hres;
         }
 
-        if(V_VT(&var) == VT_DISPATCH)
-            prot = iface_to_jsdisp((IUnknown*)V_DISPATCH(&var));
-        VariantClear(&var);
+        if(is_object_instance(val))
+            prot = iface_to_jsdisp((IUnknown*)get_object(val));
+        jsval_release(val);
     }
 
     hres = init_dispex(dispex, ctx, builtin_info, prot);
@@ -1005,7 +1005,7 @@ HRESULT jsdisp_get_id(jsdisp_t *jsdisp, const WCHAR *name, DWORD flags, DISPID *
     return DISP_E_UNKNOWNNAME;
 }
 
-HRESULT jsdisp_call_value(jsdisp_t *jsfunc, IDispatch *jsthis, WORD flags, unsigned argc, VARIANT *argv, jsval_t *r,
+HRESULT jsdisp_call_value(jsdisp_t *jsfunc, IDispatch *jsthis, WORD flags, unsigned argc, jsval_t *argv, jsval_t *r,
         jsexcept_t *ei)
 {
     HRESULT hres;
@@ -1022,7 +1022,7 @@ HRESULT jsdisp_call_value(jsdisp_t *jsfunc, IDispatch *jsthis, WORD flags, unsig
     return hres;
 }
 
-HRESULT jsdisp_call(jsdisp_t *disp, DISPID id, WORD flags, unsigned argc, VARIANT *argv, VARIANT *retv, jsexcept_t *ei)
+HRESULT jsdisp_call(jsdisp_t *disp, DISPID id, WORD flags, unsigned argc, jsval_t *argv, VARIANT *retv, jsexcept_t *ei)
 {
     dispex_prop_t *prop;
     jsval_t r;
@@ -1047,7 +1047,7 @@ HRESULT jsdisp_call(jsdisp_t *disp, DISPID id, WORD flags, unsigned argc, VARIAN
     return hres;
 }
 
-HRESULT jsdisp_call_name(jsdisp_t *disp, const WCHAR *name, WORD flags, unsigned argc, VARIANT *argv, jsval_t *r,
+HRESULT jsdisp_call_name(jsdisp_t *disp, const WCHAR *name, WORD flags, unsigned argc, jsval_t *argv, jsval_t *r,
         jsexcept_t *ei)
 {
     dispex_prop_t *prop;
@@ -1061,7 +1061,7 @@ HRESULT jsdisp_call_name(jsdisp_t *disp, const WCHAR *name, WORD flags, unsigned
     return invoke_prop_func(disp, to_disp(disp), prop, flags, argc, argv, r, ei, NULL);
 }
 
-HRESULT disp_call(script_ctx_t *ctx, IDispatch *disp, DISPID id, WORD flags, unsigned argc, VARIANT *argv,
+HRESULT disp_call(script_ctx_t *ctx, IDispatch *disp, DISPID id, WORD flags, unsigned argc, jsval_t *argv,
         VARIANT *retv, jsexcept_t *ei)
 {
     IDispatchEx *dispex;
@@ -1107,8 +1107,16 @@ HRESULT disp_call(script_ctx_t *ctx, IDispatch *disp, DISPID id, WORD flags, uns
         dp.rgvarg = buf;
     }
 
-    for(i=0; i<argc; i++)
-        dp.rgvarg[argc-i-1] = argv[i];
+    for(i=0; i<argc; i++) {
+        hres = jsval_to_variant(argv[i], dp.rgvarg+argc-i-1);
+        if(FAILED(hres)) {
+            while(i--)
+                VariantClear(dp.rgvarg+argc-i-1);
+            if(dp.rgvarg != buf)
+                heap_free(dp.rgvarg);
+            return hres;
+        }
+    }
 
     if(retv)
         V_VT(retv) = VT_EMPTY;
@@ -1129,6 +1137,8 @@ HRESULT disp_call(script_ctx_t *ctx, IDispatch *disp, DISPID id, WORD flags, uns
         hres = IDispatch_Invoke(disp, id, &IID_NULL, ctx->lcid, flags, &dp, retv, &ei->ei, &err);
     }
 
+    for(i=0; i<argc; i++)
+        VariantClear(dp.rgvarg+argc-i-1);
     if(dp.rgvarg != buf)
         heap_free(dp.rgvarg);
     if(FAILED(hres))
@@ -1139,7 +1149,7 @@ HRESULT disp_call(script_ctx_t *ctx, IDispatch *disp, DISPID id, WORD flags, uns
     return S_OK;
 }
 
-HRESULT disp_call_value(script_ctx_t *ctx, IDispatch *disp, IDispatch *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+HRESULT disp_call_value(script_ctx_t *ctx, IDispatch *disp, IDispatch *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsdisp;
@@ -1186,8 +1196,16 @@ HRESULT disp_call_value(script_ctx_t *ctx, IDispatch *disp, IDispatch *jsthis, W
         dp.rgvarg = buf;
     }
 
-    for(i=0; i<argc; i++)
-        dp.rgvarg[dp.cArgs-i-1] = argv[i];
+    for(i=0; i<argc; i++) {
+        hres = jsval_to_variant(argv[i], dp.rgvarg+dp.cArgs-i-1);
+        if(FAILED(hres)) {
+            while(i--)
+                VariantClear(dp.rgvarg+dp.cArgs-i-1);
+            if(dp.rgvarg != buf)
+                heap_free(dp.rgvarg);
+            return hres;
+        }
+    }
     if(jsthis) {
         V_VT(dp.rgvarg) = VT_DISPATCH;
         V_DISPATCH(dp.rgvarg) = jsthis;
@@ -1211,6 +1229,8 @@ HRESULT disp_call_value(script_ctx_t *ctx, IDispatch *disp, IDispatch *jsthis, W
         hres = IDispatch_Invoke(disp, DISPID_VALUE, &IID_NULL, ctx->lcid, flags, &dp, r ? &retv : NULL, &ei->ei, &err);
     }
 
+    for(i=0; i<argc; i++)
+        VariantClear(dp.rgvarg+dp.cArgs-i-1);
     if(dp.rgvarg != buf)
         heap_free(dp.rgvarg);
     if(FAILED(hres))
@@ -1224,7 +1244,7 @@ HRESULT disp_call_value(script_ctx_t *ctx, IDispatch *disp, IDispatch *jsthis, W
     return hres;
 }
 
-HRESULT jsdisp_propput_name(jsdisp_t *obj, const WCHAR *name, VARIANT *val, jsexcept_t *ei)
+HRESULT jsdisp_propput_name(jsdisp_t *obj, const WCHAR *name, jsval_t val, jsexcept_t *ei)
 {
     dispex_prop_t *prop;
     HRESULT hres;
@@ -1260,7 +1280,7 @@ HRESULT jsdisp_propput_dontenum(jsdisp_t *obj, const WCHAR *name, VARIANT *val)
     return VariantCopy(&prop->u.var, val);
 }
 
-HRESULT jsdisp_propput_idx(jsdisp_t *obj, DWORD idx, VARIANT *val, jsexcept_t *ei)
+HRESULT jsdisp_propput_idx(jsdisp_t *obj, DWORD idx, jsval_t val, jsexcept_t *ei)
 {
     WCHAR buf[12];
 
@@ -1270,7 +1290,7 @@ HRESULT jsdisp_propput_idx(jsdisp_t *obj, DWORD idx, VARIANT *val, jsexcept_t *e
     return jsdisp_propput_name(obj, buf, val, ei);
 }
 
-HRESULT disp_propput(script_ctx_t *ctx, IDispatch *disp, DISPID id, VARIANT *val, jsexcept_t *ei)
+HRESULT disp_propput(script_ctx_t *ctx, IDispatch *disp, DISPID id, VARIANT *var, jsexcept_t *ei)
 {
     jsdisp_t *jsdisp;
     HRESULT hres;
@@ -1278,6 +1298,11 @@ HRESULT disp_propput(script_ctx_t *ctx, IDispatch *disp, DISPID id, VARIANT *val
     jsdisp = iface_to_jsdisp((IUnknown*)disp);
     if(jsdisp) {
         dispex_prop_t *prop;
+        jsval_t val;
+
+        hres = variant_to_jsval(var, &val);
+        if(FAILED(hres))
+            return hres;
 
         prop = get_prop(jsdisp, id);
         if(prop)
@@ -1285,10 +1310,11 @@ HRESULT disp_propput(script_ctx_t *ctx, IDispatch *disp, DISPID id, VARIANT *val
         else
             hres = DISP_E_MEMBERNOTFOUND;
 
+        jsval_release(val);
         jsdisp_release(jsdisp);
     }else {
         DISPID dispid = DISPID_PROPERTYPUT;
-        DISPPARAMS dp  = {val, &dispid, 1, 1};
+        DISPPARAMS dp  = {var, &dispid, 1, 1};
         IDispatchEx *dispex;
 
         hres = IDispatch_QueryInterface(disp, &IID_IDispatchEx, (void**)&dispex);
@@ -1307,7 +1333,7 @@ HRESULT disp_propput(script_ctx_t *ctx, IDispatch *disp, DISPID id, VARIANT *val
     return hres;
 }
 
-HRESULT jsdisp_propget_name(jsdisp_t *obj, const WCHAR *name, VARIANT *var, jsexcept_t *ei)
+HRESULT jsdisp_propget_name(jsdisp_t *obj, const WCHAR *name, jsval_t *val, jsexcept_t *ei)
 {
     DISPPARAMS dp = {NULL, NULL, 0, 0};
     dispex_prop_t *prop;
@@ -1317,14 +1343,15 @@ HRESULT jsdisp_propget_name(jsdisp_t *obj, const WCHAR *name, VARIANT *var, jsex
     if(FAILED(hres))
         return hres;
 
-    V_VT(var) = VT_EMPTY;
-    if(!prop || prop->type==PROP_DELETED)
+    if(!prop || prop->type==PROP_DELETED) {
+        *val = jsval_undefined();
         return S_OK;
+    }
 
-    return prop_get(obj, prop, &dp, var, ei, NULL);
+    return prop_get(obj, prop, &dp, val, ei, NULL);
 }
 
-HRESULT jsdisp_get_idx(jsdisp_t *obj, DWORD idx, VARIANT *var, jsexcept_t *ei)
+HRESULT jsdisp_get_idx(jsdisp_t *obj, DWORD idx, jsval_t *r, jsexcept_t *ei)
 {
     WCHAR name[12];
     DISPPARAMS dp = {NULL, NULL, 0, 0};
@@ -1339,14 +1366,15 @@ HRESULT jsdisp_get_idx(jsdisp_t *obj, DWORD idx, VARIANT *var, jsexcept_t *ei)
     if(FAILED(hres))
         return hres;
 
-    V_VT(var) = VT_EMPTY;
-    if(!prop || prop->type==PROP_DELETED)
+    if(!prop || prop->type==PROP_DELETED) {
+        *r = jsval_undefined();
         return DISP_E_UNKNOWNNAME;
+    }
 
-    return prop_get(obj, prop, &dp, var, ei, NULL);
+    return prop_get(obj, prop, &dp, r, ei, NULL);
 }
 
-HRESULT jsdisp_propget(jsdisp_t *jsdisp, DISPID id, VARIANT *val, jsexcept_t *ei)
+HRESULT jsdisp_propget(jsdisp_t *jsdisp, DISPID id, jsval_t *val, jsexcept_t *ei)
 {
     DISPPARAMS dp  = {NULL,NULL,0,0};
     dispex_prop_t *prop;
@@ -1355,7 +1383,6 @@ HRESULT jsdisp_propget(jsdisp_t *jsdisp, DISPID id, VARIANT *val, jsexcept_t *ei
     if(!prop)
         return DISP_E_MEMBERNOTFOUND;
 
-    V_VT(val) = VT_EMPTY;
     return prop_get(jsdisp, prop, &dp, val, ei, NULL);
 }
 
@@ -1368,8 +1395,13 @@ HRESULT disp_propget(script_ctx_t *ctx, IDispatch *disp, DISPID id, VARIANT *val
 
     jsdisp = iface_to_jsdisp((IUnknown*)disp);
     if(jsdisp) {
-        hres = jsdisp_propget(jsdisp, id, val, ei);
+        jsval_t v;
+        hres = jsdisp_propget(jsdisp, id, &v, ei);
         jsdisp_release(jsdisp);
+        if(SUCCEEDED(hres)) {
+            hres = jsval_to_variant(v, val);
+            jsval_release(v);
+        }
         return hres;
     }
 
diff --git a/dlls/jscript/engine.c b/dlls/jscript/engine.c
index 26258ec4eea..4575a79133d 100644
--- a/dlls/jscript/engine.c
+++ b/dlls/jscript/engine.c
@@ -184,7 +184,7 @@ static HRESULT stack_pop_object(exec_ctx_t *ctx, IDispatch **r)
 
 static inline HRESULT stack_pop_int(exec_ctx_t *ctx, INT *r)
 {
-    return to_int32(ctx->script, stack_pop(ctx), ctx->ei, r);
+    return to_int32_var(ctx->script, stack_pop(ctx), ctx->ei, r);
 }
 
 static inline HRESULT stack_pop_uint(exec_ctx_t *ctx, DWORD *r)
@@ -385,7 +385,7 @@ static HRESULT disp_get_id(script_ctx_t *ctx, IDispatch *disp, BSTR name, DWORD
     return hres;
 }
 
-static inline BOOL is_null_var(const VARIANT *v)
+static inline BOOL var_is_null(const VARIANT *v)
 {
     return V_VT(v) == VT_NULL || (V_VT(v) == VT_DISPATCH && !V_DISPATCH(v));
 }
@@ -442,8 +442,8 @@ static HRESULT equal2_values(VARIANT *lval, VARIANT *rval, BOOL *ret)
     if(V_VT(lval) != V_VT(rval)) {
         if(is_num_vt(V_VT(lval)) && is_num_vt(V_VT(rval)))
             *ret = num_val(lval) == num_val(rval);
-        else if(is_null_var(lval))
-            *ret = is_null_var(rval);
+        else if(var_is_null(lval))
+            *ret = var_is_null(rval);
         else
             *ret = FALSE;
         return S_OK;
@@ -591,13 +591,19 @@ static HRESULT interp_var_set(exec_ctx_t *ctx)
 {
     const BSTR name = get_op_bstr(ctx, 0);
     VARIANT *v;
+    jsval_t val;
     HRESULT hres;
 
     TRACE("%s\n", debugstr_w(name));
 
     v = stack_pop(ctx);
-    hres = jsdisp_propput_name(ctx->var_disp, name, v, ctx->ei);
+    hres = variant_to_jsval(v, &val);
     VariantClear(v);
+    if(FAILED(hres))
+        return hres;
+
+    hres = jsdisp_propput_name(ctx->var_disp, name, val, ctx->ei);
+    jsval_release(val);
     return hres;
 }
 
@@ -976,17 +982,48 @@ static HRESULT interp_refval(exec_ctx_t *ctx)
     return stack_push(ctx, &v);
 }
 
+static HRESULT convert_args(exec_ctx_t *ctx, unsigned argc, jsval_t **ret)
+{
+    VARIANT *args = stack_args(ctx, argc);
+    jsval_t *argv;
+    unsigned i;
+    HRESULT hres;
+
+    if(!argc) {
+        *ret = NULL;
+        return S_OK;
+    }
+
+    argv = heap_alloc(argc * sizeof(jsval_t));
+    if(!argv)
+        return E_OUTOFMEMORY;
+
+    for(i=0; i<argc; i++) {
+        hres = variant_to_jsval(args+i, argv+i);
+        if(FAILED(hres)) {
+            while(i--)
+                jsval_release(argv[i]);
+            heap_free(argv);
+            return hres;
+        }
+    }
+
+    *ret = argv;
+    return S_OK;
+}
+
 /* ECMA-262 3rd Edition    11.2.2 */
 static HRESULT interp_new(exec_ctx_t *ctx)
 {
-    const unsigned arg = get_op_uint(ctx, 0);
+    const unsigned argc = get_op_uint(ctx, 0);
     VARIANT *constr, v;
-    jsval_t r;
+    jsval_t r, *argv;
+    unsigned i;
     HRESULT hres;
 
-    TRACE("%d\n", arg);
+    TRACE("%d\n", argc);
 
-    constr = stack_topn(ctx, arg);
+    constr = stack_topn(ctx, argc);
 
     /* NOTE: Should use to_object here */
 
@@ -997,7 +1034,14 @@ static HRESULT interp_new(exec_ctx_t *ctx)
     else if(!V_DISPATCH(constr))
         return throw_type_error(ctx->script, ctx->ei, JS_E_INVALID_PROPERTY, NULL);
 
-    hres = disp_call_value(ctx->script, V_DISPATCH(constr), NULL, DISPATCH_CONSTRUCT, arg, stack_args(ctx, arg), &r, ctx->ei);
+    hres = convert_args(ctx, argc, &argv);
+    if(FAILED(hres))
+        return hres;
+
+    hres = disp_call_value(ctx->script, V_DISPATCH(constr), NULL, DISPATCH_CONSTRUCT, argc, argv, &r, ctx->ei);
+    for(i=0; i < argc; i++)
+        jsval_release(argv[i]);
+    heap_free(argv);
     if(FAILED(hres))
         return hres;
 
@@ -1006,7 +1050,7 @@ static HRESULT interp_new(exec_ctx_t *ctx)
     if(FAILED(hres))
         return hres;
 
-    stack_popn(ctx, arg+1);
+    stack_popn(ctx, argc+1);
     return stack_push(ctx, &v);
 }
 
@@ -1016,7 +1060,8 @@ static HRESULT interp_call(exec_ctx_t *ctx)
     const unsigned argn = get_op_uint(ctx, 0);
     const int do_ret = get_op_int(ctx, 1);
     VARIANT v, *objv;
-    jsval_t r;
+    jsval_t *argv, r;
+    unsigned i;
     HRESULT hres;
 
     TRACE("%d %d\n", argn, do_ret);
@@ -1025,8 +1070,15 @@ static HRESULT interp_call(exec_ctx_t *ctx)
     if(V_VT(objv) != VT_DISPATCH)
         return throw_type_error(ctx->script, ctx->ei, JS_E_INVALID_PROPERTY, NULL);
 
-    hres = disp_call_value(ctx->script, V_DISPATCH(objv), NULL, DISPATCH_METHOD, argn, stack_args(ctx, argn),
+    hres = convert_args(ctx, argn, &argv);
+    if(FAILED(hres))
+        return hres;
+
+    hres = disp_call_value(ctx->script, V_DISPATCH(objv), NULL, DISPATCH_METHOD, argn, argv,
             do_ret ? &r : NULL, ctx->ei);
+    for(i=0; i < argn; i++)
+        jsval_release(argv[i]);
+    heap_free(argv);
     if(FAILED(hres))
         return hres;
 
@@ -1050,6 +1102,8 @@ static HRESULT interp_call_member(exec_ctx_t *ctx)
     const unsigned argn = get_op_uint(ctx, 0);
     const int do_ret = get_op_int(ctx, 1);
     IDispatch *obj;
+    jsval_t *argv;
+    unsigned i;
     VARIANT v;
     DISPID id;
     HRESULT hres;
@@ -1060,7 +1114,14 @@ static HRESULT interp_call_member(exec_ctx_t *ctx)
     if(!obj)
         return throw_type_error(ctx->script, ctx->ei, id, NULL);
 
-    hres = disp_call(ctx->script, obj, id, DISPATCH_METHOD, argn, stack_args(ctx, argn), do_ret ? &v : NULL, ctx->ei);
+    hres = convert_args(ctx, argn, &argv);
+    if(FAILED(hres))
+        return hres;
+
+    hres = disp_call(ctx->script, obj, id, DISPATCH_METHOD, argn, argv, do_ret ? &v : NULL, ctx->ei);
+    for(i=0; i < argn; i++)
+        jsval_release(argv[i]);
+    heap_free(argv);
     if(FAILED(hres))
         return hres;
 
@@ -1225,6 +1286,7 @@ static HRESULT interp_carray(exec_ctx_t *ctx)
     const unsigned arg = get_op_uint(ctx, 0);
     jsdisp_t *array;
     VARIANT *v, r;
+    jsval_t val;
     unsigned i;
     HRESULT hres;
 
@@ -1237,7 +1299,11 @@ static HRESULT interp_carray(exec_ctx_t *ctx)
     i = arg;
     while(i--) {
         v = stack_pop(ctx);
-        hres = jsdisp_propput_idx(array, i, v, ctx->ei);
+        hres = variant_to_jsval(v, &val);
+        if(SUCCEEDED(hres)) {
+            hres = jsdisp_propput_idx(array, i, val, ctx->ei);
+            jsval_release(val);
+        }
         VariantClear(v);
         if(FAILED(hres)) {
             jsdisp_release(array);
@@ -1272,6 +1338,7 @@ static HRESULT interp_obj_prop(exec_ctx_t *ctx)
     const BSTR name = get_op_bstr(ctx, 0);
     jsdisp_t *obj;
     VARIANT *v;
+    jsval_t val;
     HRESULT hres;
 
     TRACE("%s\n", debugstr_w(name));
@@ -1281,7 +1348,11 @@ static HRESULT interp_obj_prop(exec_ctx_t *ctx)
     assert(V_VT(stack_top(ctx)) == VT_DISPATCH);
     obj = as_jsdisp(V_DISPATCH(stack_top(ctx)));
 
-    hres = jsdisp_propput_name(obj, name, v, ctx->ei);
+    hres = variant_to_jsval(v, &val);
+    if(SUCCEEDED(hres)) {
+        hres = jsdisp_propput_name(obj, name, val, ctx->ei);
+        jsval_release(val);
+    }
     VariantClear(v);
     return hres;
 }
@@ -1391,7 +1462,8 @@ static HRESULT interp_and(exec_ctx_t *ctx)
 static HRESULT interp_instanceof(exec_ctx_t *ctx)
 {
     jsdisp_t *obj, *iter, *tmp = NULL;
-    VARIANT prot, *v;
+    jsval_t prot;
+    VARIANT *v;
     BOOL ret = FALSE;
     HRESULT hres;
 
@@ -1421,11 +1493,11 @@ static HRESULT interp_instanceof(exec_ctx_t *ctx)
 
     v = stack_pop(ctx);
 
-    if(V_VT(&prot) == VT_DISPATCH) {
+    if(is_object_instance(prot)) {
         if(V_VT(v) == VT_DISPATCH)
             tmp = iface_to_jsdisp((IUnknown*)V_DISPATCH(v));
         for(iter = tmp; !ret && iter; iter = iter->prototype) {
-            hres = disp_cmp(V_DISPATCH(&prot), to_disp(iter), &ret);
+            hres = disp_cmp(get_object(prot), to_disp(iter), &ret);
             if(FAILED(hres))
                 break;
         }
@@ -1437,7 +1509,7 @@ static HRESULT interp_instanceof(exec_ctx_t *ctx)
         hres = E_FAIL;
     }
 
-    VariantClear(&prot);
+    jsval_release(prot);
     VariantClear(v);
     if(FAILED(hres))
         return hres;
@@ -2283,7 +2355,7 @@ static HRESULT interp_bneg(exec_ctx_t *ctx)
     TRACE("\n");
 
     v = stack_pop(ctx);
-    hres = to_int32(ctx->script, v, ctx->ei, &i);
+    hres = to_int32_var(ctx->script, v, ctx->ei, &i);
     VariantClear(v);
     if(FAILED(hres))
         return hres;
@@ -2391,24 +2463,33 @@ static HRESULT interp_assign(exec_ctx_t *ctx)
 /* JScript extension */
 static HRESULT interp_assign_call(exec_ctx_t *ctx)
 {
-    const unsigned arg = get_op_uint(ctx, 0);
+    const unsigned argc = get_op_uint(ctx, 0);
     IDispatch *disp;
+    jsval_t *argv;
+    unsigned i;
     VARIANT *v;
     DISPID id;
     HRESULT hres;
 
-    TRACE("%u\n", arg);
+    TRACE("%u\n", argc);
 
-    disp = stack_topn_objid(ctx, arg+1, &id);
+    disp = stack_topn_objid(ctx, argc+1, &id);
     if(!disp)
         return throw_reference_error(ctx->script, ctx->ei, JS_E_ILLEGAL_ASSIGN, NULL);
 
-    hres = disp_call(ctx->script, disp, id, DISPATCH_PROPERTYPUT, arg+1, stack_args(ctx,arg+1), NULL, ctx->ei);
+    hres = convert_args(ctx, argc+1, &argv);
+    if(FAILED(hres))
+        return hres;
+
+    hres = disp_call(ctx->script, disp, id, DISPATCH_PROPERTYPUT, argc+1, argv, NULL, ctx->ei);
+    for(i=0; i < argc; i++)
+        jsval_release(argv[i]);
+    heap_free(argv);
     if(FAILED(hres))
         return hres;
 
     v = stack_pop(ctx);
-    stack_popn(ctx, arg+2);
+    stack_popn(ctx, argc+2);
     return stack_push(ctx, v);
 }
 
@@ -2513,7 +2594,13 @@ static HRESULT unwind_exception(exec_ctx_t *ctx)
 
         hres = create_dispex(ctx->script, NULL, NULL, &scope_obj);
         if(SUCCEEDED(hres)) {
-            hres = jsdisp_propput_name(scope_obj, ident, &except_val, ctx->ei);
+            jsval_t val;
+
+            hres = variant_to_jsval(&except_val, &val);
+            if(SUCCEEDED(hres)) {
+                hres = jsdisp_propput_name(scope_obj, ident, val, ctx->ei);
+                jsval_release(val);
+            }
             if(FAILED(hres))
                 jsdisp_release(scope_obj);
         }
@@ -2570,6 +2657,7 @@ static HRESULT enter_bytecode(script_ctx_t *ctx, bytecode_t *code, function_code
 
     while(exec_ctx->ip != -1) {
         op = code->instrs[exec_ctx->ip].op;
+        TRACE("top %d\n", exec_ctx->top);
         hres = op_funcs[op](exec_ctx);
         if(FAILED(hres)) {
             TRACE("EXCEPTION\n");
@@ -2618,7 +2706,6 @@ HRESULT exec_source(exec_ctx_t *ctx, bytecode_t *code, function_code_t *func, BO
 
     for(i = 0; i < func->func_cnt; i++) {
         jsdisp_t *func_obj;
-        VARIANT var;
 
         if(!func->funcs[i].name)
             continue;
@@ -2627,8 +2714,7 @@ HRESULT exec_source(exec_ctx_t *ctx, bytecode_t *code, function_code_t *func, BO
         if(FAILED(hres))
             return hres;
 
-        var_set_jsdisp(&var, func_obj);
-        hres = jsdisp_propput_name(ctx->var_disp, func->funcs[i].name, &var, ei);
+        hres = jsdisp_propput_name(ctx->var_disp, func->funcs[i].name, jsval_obj(func_obj), ei);
         jsdisp_release(func_obj);
         if(FAILED(hres))
             return hres;
diff --git a/dlls/jscript/error.c b/dlls/jscript/error.c
index 67ccf0d4c6e..407bd3ba5a2 100644
--- a/dlls/jscript/error.c
+++ b/dlls/jscript/error.c
@@ -35,11 +35,11 @@ static const WCHAR toStringW[] = {'t','o','S','t','r','i','n','g',0};
 
 /* ECMA-262 3rd Edition    15.11.4.4 */
 static HRESULT Error_toString(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsthis;
     BSTR name = NULL, msg = NULL, ret = NULL;
-    VARIANT v;
+    jsval_t v;
     HRESULT hres;
 
     static const WCHAR object_errorW[] = {'[','o','b','j','e','c','t',' ','E','r','r','o','r',']',0};
@@ -61,9 +61,9 @@ static HRESULT Error_toString(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
     if(FAILED(hres))
         return hres;
 
-    if(V_VT(&v) != VT_EMPTY) {
-        hres = to_string(ctx, &v, ei, &name);
-        VariantClear(&v);
+    if(!is_undefined(v)) {
+        hres = to_string_jsval(ctx, v, ei, &name);
+        jsval_release(v);
         if(FAILED(hres))
             return hres;
         if(!*name) {
@@ -74,9 +74,9 @@ static HRESULT Error_toString(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
 
     hres = jsdisp_propget_name(jsthis, messageW, &v, ei);
     if(SUCCEEDED(hres)) {
-        if(V_VT(&v) != VT_EMPTY) {
-            hres = to_string(ctx, &v, ei, &msg);
-            VariantClear(&v);
+        if(!is_undefined(v)) {
+            hres = to_string_jsval(ctx, v, ei, &msg);
+            jsval_release(v);
             if(SUCCEEDED(hres) && !*msg) {
                 SysFreeString(msg);
                 msg = NULL;
@@ -124,7 +124,7 @@ static HRESULT Error_toString(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
 }
 
 static HRESULT Error_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
 
@@ -189,28 +189,26 @@ static HRESULT create_error(script_ctx_t *ctx, jsdisp_t *constr,
         UINT number, const WCHAR *msg, jsdisp_t **ret)
 {
     jsdisp_t *err;
-    VARIANT v;
+    BSTR str;
     HRESULT hres;
 
     hres = alloc_error(ctx, NULL, constr, &err);
     if(FAILED(hres))
         return hres;
 
-    num_set_int(&v, number);
-    hres = jsdisp_propput_name(err, numberW, &v, NULL/*FIXME*/);
+    hres = jsdisp_propput_name(err, numberW, jsval_number((INT)number), NULL/*FIXME*/);
     if(FAILED(hres)) {
         jsdisp_release(err);
         return hres;
     }
 
-    V_VT(&v) = VT_BSTR;
-    if(msg) V_BSTR(&v) = SysAllocString(msg);
-    else V_BSTR(&v) = SysAllocStringLen(NULL, 0);
-    if(V_BSTR(&v)) {
-        hres = jsdisp_propput_name(err, messageW, &v, NULL/*FIXME*/);
+    if(msg) str = SysAllocString(msg);
+    else str = SysAllocStringLen(NULL, 0);
+    if(str) {
+        hres = jsdisp_propput_name(err, messageW, jsval_string(str), NULL/*FIXME*/);
         if(SUCCEEDED(hres))
-            hres = jsdisp_propput_name(err, descriptionW, &v, NULL/*FIXME*/);
-        SysFreeString(V_BSTR(&v));
+            hres = jsdisp_propput_name(err, descriptionW, jsval_string(str), NULL/*FIXME*/);
+        SysFreeString(str);
     }else {
         hres = E_OUTOFMEMORY;
     }
@@ -223,7 +221,7 @@ static HRESULT create_error(script_ctx_t *ctx, jsdisp_t *constr,
     return S_OK;
 }
 
-static HRESULT error_constr(script_ctx_t *ctx, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT error_constr(script_ctx_t *ctx, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei, jsdisp_t *constr) {
     jsdisp_t *err;
     UINT num = 0;
@@ -233,18 +231,18 @@ static HRESULT error_constr(script_ctx_t *ctx, WORD flags, unsigned argc, VARIAN
     if(argc) {
         double n;
 
-        hres = to_number(ctx, argv, ei, &n);
+        hres = to_number_jsval(ctx, argv[0], ei, &n);
         if(FAILED(hres)) /* FIXME: really? */
             n = NAN;
         if(isnan(n))
-            hres = to_string(ctx, argv, ei, &msg);
+            hres = to_string_jsval(ctx, argv[0], ei, &msg);
         if(FAILED(hres))
             return hres;
         num = n;
     }
 
     if(argc>1 && !msg) {
-        hres = to_string(ctx, argv+1, ei, &msg);
+        hres = to_string_jsval(ctx, argv[1], ei, &msg);
         if(FAILED(hres))
             return hres;
     }
@@ -271,56 +269,56 @@ static HRESULT error_constr(script_ctx_t *ctx, WORD flags, unsigned argc, VARIAN
 }
 
 static HRESULT ErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->error_constr);
 }
 
 static HRESULT EvalErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->eval_error_constr);
 }
 
 static HRESULT RangeErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->range_error_constr);
 }
 
 static HRESULT ReferenceErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->reference_error_constr);
 }
 
 static HRESULT RegExpErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->regexp_error_constr);
 }
 
 static HRESULT SyntaxErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->syntax_error_constr);
 }
 
 static HRESULT TypeErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->type_error_constr);
 }
 
 static HRESULT URIErrorConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
     return error_constr(ctx, flags, argc, argv, r, ei, ctx->uri_error_constr);
@@ -348,7 +346,7 @@ HRESULT init_error_constr(script_ctx_t *ctx, jsdisp_t *object_prototype)
 
     jsdisp_t *err;
     INT i;
-    VARIANT v;
+    BSTR str;
     HRESULT hres;
 
     for(i=0; i < sizeof(names)/sizeof(names[0]); i++) {
@@ -356,21 +354,19 @@ HRESULT init_error_constr(script_ctx_t *ctx, jsdisp_t *object_prototype)
         if(FAILED(hres))
             return hres;
 
-        V_VT(&v) = VT_BSTR;
-        V_BSTR(&v) = SysAllocString(names[i]);
-        if(!V_BSTR(&v)) {
+        str = SysAllocString(names[i]);
+        if(!str) {
             jsdisp_release(err);
             return E_OUTOFMEMORY;
         }
 
-        hres = jsdisp_propput_name(err, nameW, &v, NULL/*FIXME*/);
-
+        hres = jsdisp_propput_name(err, nameW, jsval_string(str), NULL/*FIXME*/);
+        SysFreeString(str);
         if(SUCCEEDED(hres))
             hres = create_builtin_constructor(ctx, constr_val[i], names[i], NULL,
                     PROPF_CONSTR|1, err, constr_addr[i]);
 
         jsdisp_release(err);
-        VariantClear(&v);
         if(FAILED(hres))
             return hres;
     }
diff --git a/dlls/jscript/function.c b/dlls/jscript/function.c
index 197b2728e10..cfeb2691a62 100644
--- a/dlls/jscript/function.c
+++ b/dlls/jscript/function.c
@@ -55,18 +55,15 @@ static const WCHAR applyW[] = {'a','p','p','l','y',0};
 static const WCHAR callW[] = {'c','a','l','l',0};
 static const WCHAR argumentsW[] = {'a','r','g','u','m','e','n','t','s',0};
 
-static HRESULT init_parameters(jsdisp_t *var_disp, FunctionInstance *function, unsigned argc, VARIANT *argv,
+static HRESULT init_parameters(jsdisp_t *var_disp, FunctionInstance *function, unsigned argc, jsval_t *argv,
         jsexcept_t *ei)
 {
-    VARIANT var_empty;
     DWORD i=0;
     HRESULT hres;
 
-    V_VT(&var_empty) = VT_EMPTY;
-
     for(i=0; i < function->func_code->param_cnt; i++) {
         hres = jsdisp_propput_name(var_disp, function->func_code->params[i],
-                i < argc ? argv+i : &var_empty, ei);
+                i < argc ? argv[i] : jsval_undefined(), ei);
         if(FAILED(hres))
             return hres;
     }
@@ -74,7 +71,7 @@ static HRESULT init_parameters(jsdisp_t *var_disp, FunctionInstance *function, u
     return S_OK;
 }
 
-static HRESULT Arguments_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Arguments_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
@@ -89,11 +86,10 @@ static const builtin_info_t Arguments_info = {
     NULL
 };
 
-static HRESULT create_arguments(script_ctx_t *ctx, IDispatch *calee, unsigned argc, VARIANT *argv,
+static HRESULT create_arguments(script_ctx_t *ctx, IDispatch *calee, unsigned argc, jsval_t *argv,
         jsexcept_t *ei, jsdisp_t **ret)
 {
     jsdisp_t *args;
-    VARIANT var;
     DWORD i;
     HRESULT hres;
 
@@ -110,20 +106,16 @@ static HRESULT create_arguments(script_ctx_t *ctx, IDispatch *calee, unsigned ar
     }
 
     for(i=0; i < argc; i++) {
-        hres = jsdisp_propput_idx(args, i, argv+i, ei);
+        hres = jsdisp_propput_idx(args, i, argv[i], ei);
         if(FAILED(hres))
             break;
     }
 
     if(SUCCEEDED(hres)) {
-        num_set_int(&var, argc);
-        hres = jsdisp_propput_name(args, lengthW, &var, ei);
+        hres = jsdisp_propput_name(args, lengthW, jsval_number(argc), ei);
 
-        if(SUCCEEDED(hres)) {
-            V_VT(&var) = VT_DISPATCH;
-            V_DISPATCH(&var) = calee;
-            hres = jsdisp_propput_name(args, caleeW, &var, ei);
-        }
+        if(SUCCEEDED(hres))
+            hres = jsdisp_propput_name(args, caleeW, jsval_disp(calee), ei);
     }
 
     if(FAILED(hres)) {
@@ -136,18 +128,16 @@ static HRESULT create_arguments(script_ctx_t *ctx, IDispatch *calee, unsigned ar
 }
 
 static HRESULT create_var_disp(script_ctx_t *ctx, FunctionInstance *function, jsdisp_t *arg_disp,
-        unsigned argc, VARIANT *argv, jsexcept_t *ei, jsdisp_t **ret)
+        unsigned argc, jsval_t *argv, jsexcept_t *ei, jsdisp_t **ret)
 {
     jsdisp_t *var_disp;
-    VARIANT var;
     HRESULT hres;
 
     hres = create_dispex(ctx, NULL, NULL, &var_disp);
     if(FAILED(hres))
         return hres;
 
-    var_set_jsdisp(&var, arg_disp);
-    hres = jsdisp_propput_name(var_disp, argumentsW, &var, ei);
+    hres = jsdisp_propput_name(var_disp, argumentsW, jsval_obj(arg_disp), ei);
     if(SUCCEEDED(hres))
         hres = init_parameters(var_disp, function, argc, argv, ei);
     if(FAILED(hres)) {
@@ -159,7 +149,7 @@ static HRESULT create_var_disp(script_ctx_t *ctx, FunctionInstance *function, js
     return S_OK;
 }
 
-static HRESULT invoke_source(script_ctx_t *ctx, FunctionInstance *function, IDispatch *this_obj, unsigned argc, VARIANT *argv,
+static HRESULT invoke_source(script_ctx_t *ctx, FunctionInstance *function, IDispatch *this_obj, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *var_disp, *arg_disp;
@@ -207,7 +197,7 @@ static HRESULT invoke_source(script_ctx_t *ctx, FunctionInstance *function, IDis
     return hres;
 }
 
-static HRESULT invoke_constructor(script_ctx_t *ctx, FunctionInstance *function, unsigned argc, VARIANT *argv,
+static HRESULT invoke_constructor(script_ctx_t *ctx, FunctionInstance *function, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *this_obj;
@@ -234,7 +224,7 @@ static HRESULT invoke_constructor(script_ctx_t *ctx, FunctionInstance *function,
     return S_OK;
 }
 
-static HRESULT invoke_value_proc(script_ctx_t *ctx, FunctionInstance *function, IDispatch *this_disp, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT invoke_value_proc(script_ctx_t *ctx, FunctionInstance *function, IDispatch *this_disp, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     vdisp_t vthis;
@@ -254,7 +244,7 @@ static HRESULT invoke_value_proc(script_ctx_t *ctx, FunctionInstance *function,
 }
 
 static HRESULT call_function(script_ctx_t *ctx, FunctionInstance *function, IDispatch *this_obj,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     if(function->value_proc)
         return invoke_value_proc(ctx, function, this_obj, DISPATCH_METHOD, argc, argv, r, ei);
@@ -291,7 +281,7 @@ static HRESULT function_to_string(FunctionInstance *function, BSTR *ret)
     return S_OK;
 }
 
-HRESULT Function_invoke(jsdisp_t *func_this, IDispatch *jsthis, WORD flags, unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+HRESULT Function_invoke(jsdisp_t *func_this, IDispatch *jsthis, WORD flags, unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *function;
 
@@ -310,7 +300,7 @@ HRESULT Function_invoke(jsdisp_t *func_this, IDispatch *jsthis, WORD flags, unsi
     return invoke_source(function->dispex.ctx, function, jsthis, argc, argv, r, ei);
 }
 
-static HRESULT Function_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Function_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *This = function_from_vdisp(jsthis);
@@ -329,7 +319,7 @@ static HRESULT Function_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return S_OK;
 }
 
-static HRESULT Function_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Function_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *function;
@@ -352,32 +342,32 @@ static HRESULT Function_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return S_OK;
 }
 
-static HRESULT array_to_args(script_ctx_t *ctx, jsdisp_t *arg_array, jsexcept_t *ei, unsigned *argc, VARIANT **ret)
+static HRESULT array_to_args(script_ctx_t *ctx, jsdisp_t *arg_array, jsexcept_t *ei, unsigned *argc, jsval_t **ret)
 {
-    VARIANT var, *argv;
+    jsval_t *argv, val;
     DWORD length, i;
     HRESULT hres;
 
-    hres = jsdisp_propget_name(arg_array, lengthW, &var, ei);
+    hres = jsdisp_propget_name(arg_array, lengthW, &val, ei);
     if(FAILED(hres))
         return hres;
 
-    hres = to_uint32(ctx, &var, ei, &length);
-    VariantClear(&var);
+    hres = to_uint32_jsval(ctx, val, ei, &length);
+    jsval_release(val);
     if(FAILED(hres))
         return hres;
 
-    argv = heap_alloc(length * sizeof(VARIANT));
+    argv = heap_alloc(length * sizeof(*argv));
     if(!argv)
         return E_OUTOFMEMORY;
 
     for(i=0; i<length; i++) {
         hres = jsdisp_get_idx(arg_array, i, argv+i, ei);
-        if(hres == DISP_E_UNKNOWNNAME)
-            V_VT(argv+i) = VT_EMPTY;
-        else if(FAILED(hres)) {
+        if(hres == DISP_E_UNKNOWNNAME) {
+            argv[i] = jsval_undefined();
+        }else if(FAILED(hres)) {
             while(i--)
-                VariantClear(argv+i);
+                jsval_release(argv[i]);
             heap_free(argv);
             return hres;
         }
@@ -388,11 +378,11 @@ static HRESULT array_to_args(script_ctx_t *ctx, jsdisp_t *arg_array, jsexcept_t
     return S_OK;
 }
 
-static HRESULT Function_apply(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Function_apply(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *function;
-    VARIANT *args = NULL;
+    jsval_t *args = NULL;
     unsigned i, cnt = 0;
     IDispatch *this_obj = NULL;
     HRESULT hres = S_OK;
@@ -403,8 +393,8 @@ static HRESULT Function_apply(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
         return throw_type_error(ctx, ei, JS_E_FUNCTION_EXPECTED, NULL);
 
     if(argc) {
-        if(V_VT(argv) != VT_EMPTY && V_VT(argv) != VT_NULL) {
-            hres = to_object(ctx, argv, &this_obj);
+        if(!is_undefined(argv[0]) && !is_null(argv[0])) {
+            hres = to_object_jsval(ctx, argv[0], &this_obj);
             if(FAILED(hres))
                 return hres;
         }
@@ -413,8 +403,8 @@ static HRESULT Function_apply(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     if(argc >= 2) {
         jsdisp_t *arg_array = NULL;
 
-        if(V_VT(argv+1) == VT_DISPATCH) {
-            arg_array = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv+1));
+        if(is_object_instance(argv[1])) {
+            arg_array = iface_to_jsdisp((IUnknown*)get_object(argv[1]));
             if(arg_array &&
                (!is_class(arg_array, JSCLASS_ARRAY) && !is_class(arg_array, JSCLASS_ARGUMENTS) )) {
                 jsdisp_release(arg_array);
@@ -437,12 +427,12 @@ static HRESULT Function_apply(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     if(this_obj)
         IDispatch_Release(this_obj);
     for(i=0; i < cnt; i++)
-        VariantClear(args+i);
+        jsval_release(args[i]);
     heap_free(args);
     return hres;
 }
 
-static HRESULT Function_call(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Function_call(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *function;
@@ -456,8 +446,8 @@ static HRESULT Function_call(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
         return throw_type_error(ctx, ei, JS_E_FUNCTION_EXPECTED, NULL);
 
     if(argc) {
-        if(V_VT(argv) != VT_EMPTY && V_VT(argv) != VT_NULL) {
-            hres = to_object(ctx, argv, &this_obj);
+        if(!is_undefined(argv[0]) && !is_null(argv[0])) {
+            hres = to_object_jsval(ctx, argv[0], &this_obj);
             if(FAILED(hres))
                 return hres;
         }
@@ -472,7 +462,7 @@ static HRESULT Function_call(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return hres;
 }
 
-HRESULT Function_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+HRESULT Function_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *function;
@@ -516,7 +506,7 @@ HRESULT Function_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
 }
 
 static HRESULT Function_arguments(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     FunctionInstance *function = (FunctionInstance*)jsthis->u.jsdisp;
     HRESULT hres = S_OK;
@@ -609,12 +599,9 @@ static HRESULT create_function(script_ctx_t *ctx, const builtin_info_t *builtin_
 static HRESULT set_prototype(script_ctx_t *ctx, jsdisp_t *dispex, jsdisp_t *prototype)
 {
     jsexcept_t jsexcept;
-    VARIANT var;
 
-    var_set_jsdisp(&var, prototype);
     memset(&jsexcept, 0, sizeof(jsexcept));
-
-    return jsdisp_propput_name(dispex, prototypeW, &var, &jsexcept);
+    return jsdisp_propput_name(dispex, prototypeW, jsval_obj(prototype), &jsexcept);
 }
 
 HRESULT create_builtin_function(script_ctx_t *ctx, builtin_invoke_t value_proc, const WCHAR *name,
@@ -716,7 +703,7 @@ HRESULT create_source_function(script_ctx_t *ctx, bytecode_t *code, function_cod
     return S_OK;
 }
 
-static HRESULT construct_function(script_ctx_t *ctx, unsigned argc, VARIANT *argv, jsexcept_t *ei, IDispatch **ret)
+static HRESULT construct_function(script_ctx_t *ctx, unsigned argc, jsval_t *argv, jsexcept_t *ei, IDispatch **ret)
 {
     WCHAR *str = NULL, *ptr;
     DWORD len = 0, l;
@@ -738,7 +725,7 @@ static HRESULT construct_function(script_ctx_t *ctx, unsigned argc, VARIANT *arg
         if(argc > 2)
             len = (argc-2)*2; /* separating commas */
         for(i=0; i < argc; i++) {
-            hres = to_string(ctx, argv+i, ei, params+i);
+            hres = to_string_jsval(ctx, argv[i], ei, params+i);
             if(FAILED(hres))
                 break;
             len += SysStringLen(params[i]);
@@ -803,7 +790,7 @@ static HRESULT construct_function(script_ctx_t *ctx, unsigned argc, VARIANT *arg
     return S_OK;
 }
 
-static HRESULT FunctionConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT FunctionConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     HRESULT hres;
@@ -829,7 +816,7 @@ static HRESULT FunctionConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
     return S_OK;
 }
 
-static HRESULT FunctionProt_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT FunctionProt_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
diff --git a/dlls/jscript/global.c b/dlls/jscript/global.c
index f486a0194fa..97c580473b4 100644
--- a/dlls/jscript/global.c
+++ b/dlls/jscript/global.c
@@ -114,7 +114,7 @@ static WCHAR int_to_char(int i)
     return 'A'+i-10;
 }
 
-static HRESULT constructor_call(jsdisp_t *constr, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT constructor_call(jsdisp_t *constr, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     if(flags != DISPATCH_PROPERTYGET)
@@ -124,7 +124,7 @@ static HRESULT constructor_call(jsdisp_t *constr, WORD flags, unsigned argc, VAR
     return S_OK;
 }
 
-static HRESULT JSGlobal_Array(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Array(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -132,7 +132,7 @@ static HRESULT JSGlobal_Array(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return constructor_call(ctx->array_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Boolean(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Boolean(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -140,7 +140,7 @@ static HRESULT JSGlobal_Boolean(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return constructor_call(ctx->bool_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Date(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Date(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -148,7 +148,7 @@ static HRESULT JSGlobal_Date(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return constructor_call(ctx->date_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Error(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Error(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -156,7 +156,7 @@ static HRESULT JSGlobal_Error(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return constructor_call(ctx->error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_EvalError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_EvalError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -164,7 +164,7 @@ static HRESULT JSGlobal_EvalError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return constructor_call(ctx->eval_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_RangeError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_RangeError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -172,7 +172,7 @@ static HRESULT JSGlobal_RangeError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
     return constructor_call(ctx->range_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_RegExpError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_RegExpError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -180,7 +180,7 @@ static HRESULT JSGlobal_RegExpError(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
     return constructor_call(ctx->regexp_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_ReferenceError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_ReferenceError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -188,7 +188,7 @@ static HRESULT JSGlobal_ReferenceError(script_ctx_t *ctx, vdisp_t *jsthis, WORD
     return constructor_call(ctx->reference_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_SyntaxError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_SyntaxError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -196,7 +196,7 @@ static HRESULT JSGlobal_SyntaxError(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
     return constructor_call(ctx->syntax_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_TypeError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_TypeError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -204,7 +204,7 @@ static HRESULT JSGlobal_TypeError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return constructor_call(ctx->type_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_URIError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_URIError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -212,7 +212,7 @@ static HRESULT JSGlobal_URIError(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return constructor_call(ctx->uri_error_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Function(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Function(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -220,7 +220,7 @@ static HRESULT JSGlobal_Function(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return constructor_call(ctx->function_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Number(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Number(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -228,7 +228,7 @@ static HRESULT JSGlobal_Number(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return constructor_call(ctx->number_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Object(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Object(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -236,7 +236,7 @@ static HRESULT JSGlobal_Object(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return constructor_call(ctx->object_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_String(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_String(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -244,7 +244,7 @@ static HRESULT JSGlobal_String(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return constructor_call(ctx->string_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_RegExp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_RegExp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -252,7 +252,7 @@ static HRESULT JSGlobal_RegExp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return constructor_call(ctx->regexp_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_ActiveXObject(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_ActiveXObject(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -260,7 +260,7 @@ static HRESULT JSGlobal_ActiveXObject(script_ctx_t *ctx, vdisp_t *jsthis, WORD f
     return constructor_call(ctx->activex_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_VBArray(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_VBArray(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -268,14 +268,14 @@ static HRESULT JSGlobal_VBArray(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return constructor_call(ctx->vbarray_constr, flags, argc, argv, r, ei);
 }
 
-static HRESULT JSGlobal_Enumerator(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_Enumerator(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT JSGlobal_escape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_escape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR ret, str;
@@ -297,7 +297,7 @@ static HRESULT JSGlobal_escape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -345,7 +345,7 @@ static HRESULT JSGlobal_escape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.1.2.1 */
-static HRESULT JSGlobal_eval(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_eval(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     bytecode_t *code;
@@ -360,9 +360,9 @@ static HRESULT JSGlobal_eval(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
         return S_OK;
     }
 
-    if(V_VT(argv) != VT_BSTR) {
+    if(!is_string(argv[0])) {
         if(r)
-            return variant_to_jsval(argv, r);
+            return jsval_copy(argv[0], r);
         return S_OK;
     }
 
@@ -371,10 +371,10 @@ static HRESULT JSGlobal_eval(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
         return E_UNEXPECTED;
     }
 
-    TRACE("parsing %s\n", debugstr_w(V_BSTR(argv)));
-    hres = compile_script(ctx, V_BSTR(argv), NULL, TRUE, FALSE, &code);
+    TRACE("parsing %s\n", debugstr_jsval(argv[0]));
+    hres = compile_script(ctx, get_string(argv[0]), NULL, TRUE, FALSE, &code);
     if(FAILED(hres)) {
-        WARN("parse (%s) failed: %08x\n", debugstr_w(V_BSTR(argv)), hres);
+        WARN("parse (%s) failed: %08x\n", debugstr_jsval(argv[0]), hres);
         return throw_syntax_error(ctx, ei, hres, NULL);
     }
 
@@ -390,7 +390,7 @@ static HRESULT JSGlobal_eval(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return hres;
 }
 
-static HRESULT JSGlobal_isNaN(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_isNaN(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BOOL ret = TRUE;
@@ -400,7 +400,7 @@ static HRESULT JSGlobal_isNaN(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     TRACE("\n");
 
     if(argc) {
-        hres = to_number(ctx, argv, ei, &n);
+        hres = to_number_jsval(ctx, argv[0], ei, &n);
         if(FAILED(hres))
             return hres;
 
@@ -413,7 +413,7 @@ static HRESULT JSGlobal_isNaN(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return S_OK;
 }
 
-static HRESULT JSGlobal_isFinite(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_isFinite(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BOOL ret = FALSE;
@@ -424,7 +424,7 @@ static HRESULT JSGlobal_isFinite(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     if(argc) {
         double n;
 
-        hres = to_number(ctx, argv, ei, &n);
+        hres = to_number_jsval(ctx, argv[0], ei, &n);
         if(FAILED(hres))
             return hres;
 
@@ -448,7 +448,7 @@ static INT char_to_int(WCHAR c)
     return 100;
 }
 
-static HRESULT JSGlobal_parseInt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_parseInt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BOOL neg = FALSE, empty = TRUE;
@@ -465,7 +465,7 @@ static HRESULT JSGlobal_parseInt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     }
 
     if(argc >= 2) {
-        hres = to_int32(ctx, argv+1, ei, &radix);
+        hres = to_int32(ctx, argv[1], ei, &radix);
         if(FAILED(hres))
             return hres;
 
@@ -477,7 +477,7 @@ static HRESULT JSGlobal_parseInt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
         }
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -528,7 +528,7 @@ static HRESULT JSGlobal_parseInt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return S_OK;
 }
 
-static HRESULT JSGlobal_parseFloat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_parseFloat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     LONGLONG d = 0, hlp;
@@ -544,7 +544,7 @@ static HRESULT JSGlobal_parseFloat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flag
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &val_str);
+    hres = to_string_jsval(ctx, argv[0], ei, &val_str);
     if(FAILED(hres))
         return hres;
 
@@ -635,7 +635,7 @@ static inline int hex_to_int(const WCHAR wch) {
     return -1;
 }
 
-static HRESULT JSGlobal_unescape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_unescape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR ret, str;
@@ -656,7 +656,7 @@ static HRESULT JSGlobal_unescape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -709,14 +709,14 @@ static HRESULT JSGlobal_unescape(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return S_OK;
 }
 
-static HRESULT JSGlobal_GetObject(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_GetObject(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT JSGlobal_ScriptEngine(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_ScriptEngine(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR JScriptW[] = {'J','S','c','r','i','p','t',0};
@@ -736,7 +736,7 @@ static HRESULT JSGlobal_ScriptEngine(script_ctx_t *ctx, vdisp_t *jsthis, WORD fl
     return S_OK;
 }
 
-static HRESULT JSGlobal_ScriptEngineMajorVersion(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_ScriptEngineMajorVersion(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -746,7 +746,7 @@ static HRESULT JSGlobal_ScriptEngineMajorVersion(script_ctx_t *ctx, vdisp_t *jst
     return S_OK;
 }
 
-static HRESULT JSGlobal_ScriptEngineMinorVersion(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_ScriptEngineMinorVersion(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -756,7 +756,7 @@ static HRESULT JSGlobal_ScriptEngineMinorVersion(script_ctx_t *ctx, vdisp_t *jst
     return S_OK;
 }
 
-static HRESULT JSGlobal_ScriptEngineBuildVersion(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_ScriptEngineBuildVersion(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -766,14 +766,14 @@ static HRESULT JSGlobal_ScriptEngineBuildVersion(script_ctx_t *ctx, vdisp_t *jst
     return S_OK;
 }
 
-static HRESULT JSGlobal_CollectGarbage(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_CollectGarbage(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT JSGlobal_encodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_encodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR *ptr;
@@ -797,7 +797,7 @@ static HRESULT JSGlobal_encodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -844,7 +844,7 @@ static HRESULT JSGlobal_encodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return S_OK;
 }
 
-static HRESULT JSGlobal_decodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_decodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR str, ret;
@@ -868,7 +868,7 @@ static HRESULT JSGlobal_decodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -936,7 +936,7 @@ static HRESULT JSGlobal_decodeURI(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return S_OK;
 }
 
-static HRESULT JSGlobal_encodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_encodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR str, ret;
@@ -959,7 +959,7 @@ static HRESULT JSGlobal_encodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, W
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -1006,7 +1006,7 @@ static HRESULT JSGlobal_encodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, W
 }
 
 /* ECMA-262 3rd Edition    15.1.3.2 */
-static HRESULT JSGlobal_decodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT JSGlobal_decodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR str, ret;
@@ -1029,7 +1029,7 @@ static HRESULT JSGlobal_decodeURIComponent(script_ctx_t *ctx, vdisp_t *jsthis, W
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &str);
+    hres = to_string_jsval(ctx, argv[0], ei, &str);
     if(FAILED(hres))
         return hres;
 
@@ -1226,7 +1226,6 @@ static HRESULT init_constructors(script_ctx_t *ctx, jsdisp_t *object_prototype)
 HRESULT init_global(script_ctx_t *ctx)
 {
     jsdisp_t *math, *object_prototype;
-    VARIANT var;
     HRESULT hres;
 
     if(ctx->global)
@@ -1249,23 +1248,19 @@ HRESULT init_global(script_ctx_t *ctx)
     if(FAILED(hres))
         return hres;
 
-    var_set_jsdisp(&var, math);
-    hres = jsdisp_propput_name(ctx->global, MathW, &var, NULL/*FIXME*/);
+    hres = jsdisp_propput_name(ctx->global, MathW, jsval_obj(math), NULL/*FIXME*/);
     jsdisp_release(math);
     if(FAILED(hres))
         return hres;
 
-    V_VT(&var) = VT_EMPTY;
-    hres = jsdisp_propput_name(ctx->global, undefinedW, &var, NULL/*FIXME*/);
+    hres = jsdisp_propput_name(ctx->global, undefinedW, jsval_undefined(), NULL/*FIXME*/);
     if(FAILED(hres))
         return hres;
 
-    num_set_val(&var, NAN);
-    hres = jsdisp_propput_name(ctx->global, NaNW, &var, NULL/*FIXME*/);
+    hres = jsdisp_propput_name(ctx->global, NaNW, jsval_number(NAN), NULL/*FIXME*/);
     if(FAILED(hres))
         return hres;
 
-    num_set_val(&var, INFINITY);
-    hres = jsdisp_propput_name(ctx->global, InfinityW, &var, NULL/*FIXME*/);
+    hres = jsdisp_propput_name(ctx->global, InfinityW, jsval_number(INFINITY), NULL/*FIXME*/);
     return hres;
 }
diff --git a/dlls/jscript/jscript.h b/dlls/jscript/jscript.h
index 24125a8a888..f9fcd73c51c 100644
--- a/dlls/jscript/jscript.h
+++ b/dlls/jscript/jscript.h
@@ -153,7 +153,7 @@ static inline jsdisp_t *get_jsdisp(vdisp_t *vdisp)
     return is_jsdisp(vdisp) ? vdisp->u.jsdisp : NULL;
 }
 
-typedef HRESULT (*builtin_invoke_t)(script_ctx_t*,vdisp_t*,WORD,unsigned,VARIANT*,jsval_t*,jsexcept_t*);
+typedef HRESULT (*builtin_invoke_t)(script_ctx_t*,vdisp_t*,WORD,unsigned,jsval_t*,jsval_t*,jsexcept_t*);
 
 typedef struct {
     const WCHAR *name;
@@ -208,20 +208,20 @@ HRESULT create_dispex(script_ctx_t*,const builtin_info_t*,jsdisp_t*,jsdisp_t**)
 HRESULT init_dispex(jsdisp_t*,script_ctx_t*,const builtin_info_t*,jsdisp_t*) DECLSPEC_HIDDEN;
 HRESULT init_dispex_from_constr(jsdisp_t*,script_ctx_t*,const builtin_info_t*,jsdisp_t*) DECLSPEC_HIDDEN;
 
-HRESULT disp_call(script_ctx_t*,IDispatch*,DISPID,WORD,unsigned,VARIANT*,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT disp_call_value(script_ctx_t*,IDispatch*,IDispatch*,WORD,unsigned,VARIANT*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_call_value(jsdisp_t*,IDispatch*,WORD,unsigned,VARIANT*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_call(jsdisp_t*,DISPID,WORD,unsigned,VARIANT*,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_call_name(jsdisp_t*,const WCHAR*,WORD,unsigned,VARIANT*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT disp_call(script_ctx_t*,IDispatch*,DISPID,WORD,unsigned,jsval_t*,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT disp_call_value(script_ctx_t*,IDispatch*,IDispatch*,WORD,unsigned,jsval_t*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_call_value(jsdisp_t*,IDispatch*,WORD,unsigned,jsval_t*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_call(jsdisp_t*,DISPID,WORD,unsigned,jsval_t*,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_call_name(jsdisp_t*,const WCHAR*,WORD,unsigned,jsval_t*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
 HRESULT disp_propget(script_ctx_t*,IDispatch*,DISPID,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
 HRESULT disp_propput(script_ctx_t*,IDispatch*,DISPID,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_propget(jsdisp_t*,DISPID,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_propput_name(jsdisp_t*,const WCHAR*,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_propget(jsdisp_t*,DISPID,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_propput_name(jsdisp_t*,const WCHAR*,jsval_t,jsexcept_t*) DECLSPEC_HIDDEN;
 HRESULT jsdisp_propput_const(jsdisp_t*,const WCHAR*,VARIANT*) DECLSPEC_HIDDEN;
 HRESULT jsdisp_propput_dontenum(jsdisp_t*,const WCHAR*,VARIANT*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_propput_idx(jsdisp_t*,DWORD,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_propget_name(jsdisp_t*,LPCWSTR,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT jsdisp_get_idx(jsdisp_t*,DWORD,VARIANT*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_propput_idx(jsdisp_t*,DWORD,jsval_t,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_propget_name(jsdisp_t*,LPCWSTR,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT jsdisp_get_idx(jsdisp_t*,DWORD,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
 HRESULT jsdisp_get_id(jsdisp_t*,const WCHAR*,DWORD,DISPID*) DECLSPEC_HIDDEN;
 HRESULT jsdisp_delete_idx(jsdisp_t*,DWORD) DECLSPEC_HIDDEN;
 HRESULT jsdisp_is_own_prop(jsdisp_t*,BSTR,VARIANT_BOOL*) DECLSPEC_HIDDEN;
@@ -230,8 +230,8 @@ HRESULT create_builtin_function(script_ctx_t*,builtin_invoke_t,const WCHAR*,cons
         jsdisp_t*,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_builtin_constructor(script_ctx_t*,builtin_invoke_t,const WCHAR*,const builtin_info_t*,DWORD,
         jsdisp_t*,jsdisp_t**) DECLSPEC_HIDDEN;
-HRESULT Function_value(script_ctx_t*,vdisp_t*,WORD,unsigned,VARIANT*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
-HRESULT Function_invoke(jsdisp_t*,IDispatch*,WORD,unsigned,VARIANT*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT Function_value(script_ctx_t*,vdisp_t*,WORD,unsigned,jsval_t*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
+HRESULT Function_invoke(jsdisp_t*,IDispatch*,WORD,unsigned,jsval_t*,jsval_t*,jsexcept_t*) DECLSPEC_HIDDEN;
 
 HRESULT throw_eval_error(script_ctx_t*,jsexcept_t*,HRESULT,const WCHAR*) DECLSPEC_HIDDEN;
 HRESULT throw_generic_error(script_ctx_t*,jsexcept_t*,HRESULT,const WCHAR*) DECLSPEC_HIDDEN;
@@ -246,7 +246,7 @@ HRESULT create_object(script_ctx_t*,jsdisp_t*,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_math(script_ctx_t*,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_array(script_ctx_t*,DWORD,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_regexp(script_ctx_t*,const WCHAR *,int,DWORD,jsdisp_t**) DECLSPEC_HIDDEN;
-HRESULT create_regexp_var(script_ctx_t*,VARIANT*,VARIANT*,jsdisp_t**) DECLSPEC_HIDDEN;
+HRESULT create_regexp_var(script_ctx_t*,jsval_t,jsval_t*,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_string(script_ctx_t*,const WCHAR*,DWORD,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_bool(script_ctx_t*,VARIANT_BOOL,jsdisp_t**) DECLSPEC_HIDDEN;
 HRESULT create_number(script_ctx_t*,double,jsdisp_t**) DECLSPEC_HIDDEN;
@@ -260,14 +260,18 @@ typedef enum {
 
 HRESULT to_primitive(script_ctx_t*,VARIANT*,jsexcept_t*,VARIANT*, hint_t) DECLSPEC_HIDDEN;
 HRESULT to_boolean(VARIANT*,VARIANT_BOOL*) DECLSPEC_HIDDEN;
+HRESULT to_boolean_jsval(jsval_t,BOOL*) DECLSPEC_HIDDEN;
 HRESULT to_number(script_ctx_t*,VARIANT*,jsexcept_t*,double*) DECLSPEC_HIDDEN;
 HRESULT to_number_jsval(script_ctx_t*,jsval_t,jsexcept_t*,double*) DECLSPEC_HIDDEN;
-HRESULT to_integer(script_ctx_t*,VARIANT*,jsexcept_t*,double*) DECLSPEC_HIDDEN;
-HRESULT to_int32(script_ctx_t*,VARIANT*,jsexcept_t*,INT*) DECLSPEC_HIDDEN;
+HRESULT to_integer(script_ctx_t*,jsval_t,jsexcept_t*,double*) DECLSPEC_HIDDEN;
+HRESULT to_int32_var(script_ctx_t*,VARIANT*,jsexcept_t*,INT*) DECLSPEC_HIDDEN;
+HRESULT to_int32(script_ctx_t*,jsval_t,jsexcept_t*,INT*) DECLSPEC_HIDDEN;
 HRESULT to_uint32(script_ctx_t*,VARIANT*,jsexcept_t*,DWORD*) DECLSPEC_HIDDEN;
+HRESULT to_uint32_jsval(script_ctx_t*,jsval_t,jsexcept_t*,DWORD*) DECLSPEC_HIDDEN;
 HRESULT to_string(script_ctx_t*,VARIANT*,jsexcept_t*,BSTR*) DECLSPEC_HIDDEN;
 HRESULT to_string_jsval(script_ctx_t*,jsval_t,jsexcept_t*,BSTR*) DECLSPEC_HIDDEN;
 HRESULT to_object(script_ctx_t*,VARIANT*,IDispatch**) DECLSPEC_HIDDEN;
+HRESULT to_object_jsval(script_ctx_t*,jsval_t,IDispatch**) DECLSPEC_HIDDEN;
 
 HRESULT variant_change_type(script_ctx_t*,VARIANT*,VARIANT*,VARTYPE) DECLSPEC_HIDDEN;
 
@@ -491,6 +495,7 @@ static inline BOOL is_jscript_error(HRESULT hres)
 }
 
 const char *debugstr_variant(const VARIANT*) DECLSPEC_HIDDEN;
+const char *debugstr_jsval(const jsval_t) DECLSPEC_HIDDEN;
 
 HRESULT create_jscript_object(BOOL,REFIID,void**) DECLSPEC_HIDDEN;
 
diff --git a/dlls/jscript/jsutils.c b/dlls/jscript/jsutils.c
index 474f3473cf0..b0a2047674e 100644
--- a/dlls/jscript/jsutils.c
+++ b/dlls/jscript/jsutils.c
@@ -57,6 +57,29 @@ const char *debugstr_variant(const VARIANT *v)
     }
 }
 
+const char *debugstr_jsval(const jsval_t v)
+{
+    switch(v.type) {
+    case JSV_UNDEFINED:
+        return "undefined";
+    case JSV_NULL:
+        return "null";
+    case JSV_OBJECT:
+        return wine_dbg_sprintf("obj(%p)", get_object(v));
+    case JSV_STRING:
+        return debugstr_w(get_string(v));
+    case JSV_NUMBER:
+        return wine_dbg_sprintf("%lf", get_number(v));
+    case JSV_BOOL:
+        return get_bool(v) ? "true" : "false";
+    case JSV_VARIANT:
+        return debugstr_variant(get_variant(v));
+    }
+
+    assert(0);
+    return NULL;
+}
+
 #define MIN_BLOCK_SIZE  128
 #define ARENA_FREE_FILLER  0xaa
 
@@ -194,7 +217,8 @@ void jsval_release(jsval_t val)
 {
     switch(val.type) {
     case JSV_OBJECT:
-        IDispatch_Release(val.u.obj);
+        if(val.u.obj)
+            IDispatch_Release(val.u.obj);
         break;
     case JSV_STRING:
         SysFreeString(val.u.str);
@@ -224,6 +248,34 @@ HRESULT jsval_variant(jsval_t *val, VARIANT *var)
     return hres;
 }
 
+HRESULT jsval_copy(jsval_t v, jsval_t *r)
+{
+    switch(v.type) {
+    case JSV_UNDEFINED:
+    case JSV_NULL:
+    case JSV_NUMBER:
+    case JSV_BOOL:
+        *r = v;
+        return S_OK;
+    case JSV_OBJECT:
+        IDispatch_AddRef(get_object(v));
+        *r = v;
+        return S_OK;
+    case JSV_STRING: {
+        BSTR str = clone_bstr(get_string(v));
+        if(!str)
+            return E_OUTOFMEMORY;
+        *r = jsval_string(str);
+        return S_OK;
+    }
+    case JSV_VARIANT:
+        return jsval_variant(r, get_variant(v));
+    }
+
+    assert(0);
+    return E_FAIL;
+}
+
 HRESULT variant_to_jsval(VARIANT *var, jsval_t *r)
 {
     switch(V_VT(var)) {
@@ -243,20 +295,30 @@ HRESULT variant_to_jsval(VARIANT *var, jsval_t *r)
         *r = jsval_number(V_R8(var));
         return S_OK;
     case VT_BSTR: {
-        BSTR str = clone_bstr(V_BSTR(var));
-        if(!str)
-            return E_OUTOFMEMORY;
+        BSTR str;
+
+        if(V_BSTR(var)) {
+            str = clone_bstr(V_BSTR(var));
+            if(!str)
+                return E_OUTOFMEMORY;
+        }else {
+            str = NULL;
+        }
         *r = jsval_string(str);
         return S_OK;
     }
     case VT_DISPATCH: {
-        IDispatch_AddRef(V_DISPATCH(var));
+        if(V_DISPATCH(var))
+            IDispatch_AddRef(V_DISPATCH(var));
         *r = jsval_disp(V_DISPATCH(var));
         return S_OK;
     }
     case VT_I2:
+        *r = jsval_number(V_I2(var));
+        return S_OK;
     case VT_INT:
-        assert(0);
+        *r = jsval_number(V_INT(var));
+        return S_OK;
     default:
         return jsval_variant(r, var);
     }
@@ -273,14 +335,19 @@ HRESULT jsval_to_variant(jsval_t val, VARIANT *retv)
         return S_OK;
     case JSV_OBJECT:
         V_VT(retv) = VT_DISPATCH;
-        IDispatch_AddRef(val.u.obj);
+        if(val.u.obj)
+            IDispatch_AddRef(val.u.obj);
         V_DISPATCH(retv) = val.u.obj;
         return S_OK;
     case JSV_STRING:
         V_VT(retv) = VT_BSTR;
-        V_BSTR(retv) = clone_bstr(val.u.str);
-        if(!V_BSTR(retv))
-            return E_OUTOFMEMORY;
+        if(val.u.str) {
+            V_BSTR(retv) = clone_bstr(val.u.str);
+            if(!V_BSTR(retv))
+                return E_OUTOFMEMORY;
+        }else {
+            V_BSTR(retv) = NULL;
+        }
         return S_OK;
     case JSV_NUMBER:
         num_set_val(retv, val.u.n);
@@ -416,6 +483,31 @@ HRESULT to_boolean(VARIANT *v, VARIANT_BOOL *b)
     return S_OK;
 }
 
+/* ECMA-262 3rd Edition    9.2 */
+HRESULT to_boolean_jsval(jsval_t v, BOOL *ret)
+{
+    VARIANT_BOOL b;
+    VARIANT var;
+    HRESULT hres;
+
+    if(v.type == JSV_BOOL) {
+        *ret = v.u.b;
+        return S_OK;
+    }
+
+    hres = jsval_to_variant(v, &var);
+    if(FAILED(hres))
+        return hres;
+
+    hres = to_boolean(&var, &b);
+    VariantClear(&var);
+    if(FAILED(hres))
+        return hres;
+
+    *ret = !!b;
+    return S_OK;
+}
+
 static int hex_to_int(WCHAR c)
 {
     if('0' <= c && c <= '9')
@@ -590,7 +682,24 @@ HRESULT to_number_jsval(script_ctx_t *ctx, jsval_t v, jsexcept_t *ei, double *re
 }
 
 /* ECMA-262 3rd Edition    9.4 */
-HRESULT to_integer(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, double *ret)
+HRESULT to_integer(script_ctx_t *ctx, jsval_t v, jsexcept_t *ei, double *ret)
+{
+    double n;
+    HRESULT hres;
+
+    hres = to_number_jsval(ctx, v, ei, &n);
+    if(FAILED(hres))
+        return hres;
+
+    if(isnan(n))
+        *ret = 0;
+    else
+        *ret = n >= 0.0 ? floor(n) : -floor(-n);
+    return S_OK;
+}
+
+/* ECMA-262 3rd Edition    9.5 */
+HRESULT to_int32_var(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, INT *ret)
 {
     double n;
     HRESULT hres;
@@ -604,25 +713,17 @@ HRESULT to_integer(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, double *ret)
     if(FAILED(hres))
         return hres;
 
-    if(isnan(n))
-        *ret = 0;
-    else
-        *ret = n >= 0.0 ? floor(n) : -floor(-n);
+    *ret = isnan(n) || isinf(n) ? 0 : n;
     return S_OK;
 }
 
 /* ECMA-262 3rd Edition    9.5 */
-HRESULT to_int32(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, INT *ret)
+HRESULT to_int32(script_ctx_t *ctx, jsval_t v, jsexcept_t *ei, INT *ret)
 {
     double n;
     HRESULT hres;
 
-    if(V_VT(v) == VT_I4) {
-        *ret = V_I4(v);
-        return S_OK;
-    }
-
-    hres = to_number(ctx, v, ei, &n);
+    hres = to_number_jsval(ctx, v, ei, &n);
     if(FAILED(hres))
         return hres;
 
@@ -649,6 +750,21 @@ HRESULT to_uint32(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, DWORD *ret)
     return S_OK;
 }
 
+/* ECMA-262 3rd Edition    9.6 */
+HRESULT to_uint32_jsval(script_ctx_t *ctx, jsval_t v, jsexcept_t *ei, DWORD *ret)
+{
+    VARIANT var;
+    HRESULT hres;
+
+    hres = jsval_to_variant(v, &var);
+    if(FAILED(hres))
+        return hres;
+
+    hres = to_uint32(ctx, &var, ei, ret);
+    VariantClear(&var);
+    return hres;
+}
+
 static BSTR int_to_bstr(int i)
 {
     WCHAR buf[12], *p;
@@ -829,6 +945,27 @@ HRESULT to_object(script_ctx_t *ctx, VARIANT *v, IDispatch **disp)
     return S_OK;
 }
 
+/* ECMA-262 3rd Edition    9.9 */
+HRESULT to_object_jsval(script_ctx_t *ctx, jsval_t v, IDispatch **disp)
+{
+    VARIANT var;
+    HRESULT hres;
+
+    if(is_object_instance(v)) {
+        *disp = get_object(v);
+        IDispatch_AddRef(*disp);
+        return S_OK;
+    }
+
+    hres = jsval_to_variant(v, &var);
+    if(FAILED(hres))
+        return hres;
+
+    hres = to_object(ctx, &var, disp);
+    VariantClear(&var);
+    return hres;
+}
+
 HRESULT variant_change_type(script_ctx_t *ctx, VARIANT *dst, VARIANT *src, VARTYPE vt)
 {
     jsexcept_t ei;
@@ -841,7 +978,7 @@ HRESULT variant_change_type(script_ctx_t *ctx, VARIANT *dst, VARIANT *src, VARTY
     case VT_I4: {
         INT i;
 
-        hres = to_int32(ctx, src, &ei, &i);
+        hres = to_int32_var(ctx, src, &ei, &i);
         if(SUCCEEDED(hres)) {
             if(vt == VT_I4)
                 V_I4(dst) = i;
diff --git a/dlls/jscript/math.c b/dlls/jscript/math.c
index 901657d4eb3..679e37e31ab 100644
--- a/dlls/jscript/math.c
+++ b/dlls/jscript/math.c
@@ -58,7 +58,7 @@ static const WCHAR sqrtW[] = {'s','q','r','t',0};
 static const WCHAR tanW[] = {'t','a','n',0};
 
 /* ECMA-262 3rd Edition    15.8.2.12 */
-static HRESULT Math_abs(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_abs(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double d;
@@ -72,7 +72,7 @@ static HRESULT Math_abs(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &d);
+    hres = to_number_jsval(ctx, argv[0], ei, &d);
     if(FAILED(hres))
         return hres;
 
@@ -81,7 +81,7 @@ static HRESULT Math_abs(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
     return S_OK;
 }
 
-static HRESULT Math_acos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_acos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -95,7 +95,7 @@ static HRESULT Math_acos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -104,7 +104,7 @@ static HRESULT Math_acos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
     return S_OK;
 }
 
-static HRESULT Math_asin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_asin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -118,7 +118,7 @@ static HRESULT Math_asin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -127,7 +127,7 @@ static HRESULT Math_asin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
     return S_OK;
 }
 
-static HRESULT Math_atan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_atan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -141,7 +141,7 @@ static HRESULT Math_atan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -150,7 +150,7 @@ static HRESULT Math_atan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
     return S_OK;
 }
 
-static HRESULT Math_atan2(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_atan2(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x, y;
@@ -164,11 +164,11 @@ static HRESULT Math_atan2(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &y);
+    hres = to_number_jsval(ctx, argv[0], ei, &y);
     if(FAILED(hres))
         return hres;
 
-    hres = to_number(ctx, argv+1, ei, &x);
+    hres = to_number_jsval(ctx, argv[1], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -178,7 +178,7 @@ static HRESULT Math_atan2(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
 }
 
 /* ECMA-262 3rd Edition    15.8.2.6 */
-static HRESULT Math_ceil(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_ceil(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -192,7 +192,7 @@ static HRESULT Math_ceil(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -201,7 +201,7 @@ static HRESULT Math_ceil(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
     return S_OK;
 }
 
-static HRESULT Math_cos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_cos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -215,7 +215,7 @@ static HRESULT Math_cos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -224,7 +224,7 @@ static HRESULT Math_cos(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
     return S_OK;
 }
 
-static HRESULT Math_exp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_exp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -238,7 +238,7 @@ static HRESULT Math_exp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -247,7 +247,7 @@ static HRESULT Math_exp(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
     return S_OK;
 }
 
-static HRESULT Math_floor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_floor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -261,7 +261,7 @@ static HRESULT Math_floor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -270,7 +270,7 @@ static HRESULT Math_floor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
     return S_OK;
 }
 
-static HRESULT Math_log(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_log(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -284,7 +284,7 @@ static HRESULT Math_log(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -294,7 +294,7 @@ static HRESULT Math_log(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
 }
 
 /* ECMA-262 3rd Edition    15.8.2.11 */
-static HRESULT Math_max(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_max(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DOUBLE max, d;
@@ -309,12 +309,12 @@ static HRESULT Math_max(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &max);
+    hres = to_number_jsval(ctx, argv[0], ei, &max);
     if(FAILED(hres))
         return hres;
 
     for(i=1; i < argc; i++) {
-        hres = to_number(ctx, argv+i, ei, &d);
+        hres = to_number_jsval(ctx, argv[i], ei, &d);
         if(FAILED(hres))
             return hres;
 
@@ -328,7 +328,7 @@ static HRESULT Math_max(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
 }
 
 /* ECMA-262 3rd Edition    15.8.2.12 */
-static HRESULT Math_min(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_min(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DOUBLE min, d;
@@ -343,12 +343,12 @@ static HRESULT Math_min(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &min);
+    hres = to_number_jsval(ctx, argv[0], ei, &min);
     if(FAILED(hres))
         return hres;
 
     for(i=1; i < argc; i++) {
-        hres = to_number(ctx, argv+i, ei, &d);
+        hres = to_number_jsval(ctx, argv[i], ei, &d);
         if(FAILED(hres))
             return hres;
 
@@ -362,7 +362,7 @@ static HRESULT Math_min(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
 }
 
 /* ECMA-262 3rd Edition    15.8.2.13 */
-static HRESULT Math_pow(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_pow(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x, y;
@@ -376,11 +376,11 @@ static HRESULT Math_pow(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
-    hres = to_number(ctx, argv+1, ei, &y);
+    hres = to_number_jsval(ctx, argv[1], ei, &y);
     if(FAILED(hres))
         return hres;
 
@@ -390,7 +390,7 @@ static HRESULT Math_pow(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
 }
 
 /* ECMA-262 3rd Edition    15.8.2.14 */
-static HRESULT Math_random(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_random(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     UINT x;
@@ -406,7 +406,7 @@ static HRESULT Math_random(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
 }
 
 /* ECMA-262 3rd Edition    15.8.2.15 */
-static HRESULT Math_round(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_round(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -420,7 +420,7 @@ static HRESULT Math_round(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -429,7 +429,7 @@ static HRESULT Math_round(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
     return S_OK;
 }
 
-static HRESULT Math_sin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_sin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -443,7 +443,7 @@ static HRESULT Math_sin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -452,7 +452,7 @@ static HRESULT Math_sin(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
     return S_OK;
 }
 
-static HRESULT Math_sqrt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_sqrt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -466,7 +466,7 @@ static HRESULT Math_sqrt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
@@ -475,7 +475,7 @@ static HRESULT Math_sqrt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigne
     return S_OK;
 }
 
-static HRESULT Math_tan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Math_tan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double x;
@@ -489,7 +489,7 @@ static HRESULT Math_tan(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned
         return S_OK;
     }
 
-    hres = to_number(ctx, argv, ei, &x);
+    hres = to_number_jsval(ctx, argv[0], ei, &x);
     if(FAILED(hres))
         return hres;
 
diff --git a/dlls/jscript/number.c b/dlls/jscript/number.c
index 46b83ab38b3..b72ec28beb9 100644
--- a/dlls/jscript/number.c
+++ b/dlls/jscript/number.c
@@ -218,7 +218,7 @@ static inline void number_to_exponential(double val, int prec, BSTR *out)
 }
 
 /* ECMA-262 3rd Edition    15.7.4.2 */
-static HRESULT Number_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     NumberInstance *number;
@@ -233,7 +233,7 @@ static HRESULT Number_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
         return throw_type_error(ctx, ei, JS_E_NUMBER_EXPECTED, NULL);
 
     if(argc) {
-        hres = to_int32(ctx, argv, ei, &radix);
+        hres = to_int32(ctx, argv[0], ei, &radix);
         if(FAILED(hres))
             return hres;
 
@@ -341,14 +341,14 @@ static HRESULT Number_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return S_OK;
 }
 
-static HRESULT Number_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT Number_toFixed(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_toFixed(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     NumberInstance *number;
@@ -363,7 +363,7 @@ static HRESULT Number_toFixed(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
         return throw_type_error(ctx, ei, JS_E_NUMBER_EXPECTED, NULL);
 
     if(argc) {
-        hres = to_int32(ctx, argv, ei, &prec);
+        hres = to_int32(ctx, argv[0], ei, &prec);
         if(FAILED(hres))
             return hres;
 
@@ -390,7 +390,7 @@ static HRESULT Number_toFixed(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return S_OK;
 }
 
-static HRESULT Number_toExponential(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_toExponential(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     NumberInstance *number;
@@ -405,7 +405,7 @@ static HRESULT Number_toExponential(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
         return throw_type_error(ctx, ei, JS_E_NUMBER_EXPECTED, NULL);
 
     if(argc) {
-        hres = to_int32(ctx, argv, ei, &prec);
+        hres = to_int32(ctx, argv[0], ei, &prec);
         if(FAILED(hres))
             return hres;
 
@@ -434,7 +434,7 @@ static HRESULT Number_toExponential(script_ctx_t *ctx, vdisp_t *jsthis, WORD fla
     return S_OK;
 }
 
-static HRESULT Number_toPrecision(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_toPrecision(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     NumberInstance *number;
@@ -447,7 +447,7 @@ static HRESULT Number_toPrecision(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         return throw_type_error(ctx, ei, JS_E_NUMBER_EXPECTED, NULL);
 
     if(argc) {
-        hres = to_int32(ctx, argv, ei, &prec);
+        hres = to_int32(ctx, argv[0], ei, &prec);
         if(FAILED(hres))
             return hres;
 
@@ -482,7 +482,7 @@ static HRESULT Number_toPrecision(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return S_OK;
 }
 
-static HRESULT Number_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     NumberInstance *number;
@@ -497,7 +497,7 @@ static HRESULT Number_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return S_OK;
 }
 
-static HRESULT Number_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Number_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     NumberInstance *number = number_from_vdisp(jsthis);
@@ -543,7 +543,7 @@ static const builtin_info_t NumberInst_info = {
     NULL
 };
 
-static HRESULT NumberConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT NumberConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     double n;
@@ -559,7 +559,7 @@ static HRESULT NumberConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
             return S_OK;
         }
 
-        hres = to_number(ctx, argv, ei, &n);
+        hres = to_number_jsval(ctx, argv[0], ei, &n);
         if(FAILED(hres))
             return hres;
 
@@ -571,7 +571,7 @@ static HRESULT NumberConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         jsdisp_t *obj;
 
         if(argc) {
-            hres = to_number(ctx, argv, ei, &n);
+            hres = to_number_jsval(ctx, argv[0], ei, &n);
             if(FAILED(hres))
                 return hres;
         }else {
diff --git a/dlls/jscript/object.c b/dlls/jscript/object.c
index fa0e25a8c2b..a00f1c7591d 100644
--- a/dlls/jscript/object.c
+++ b/dlls/jscript/object.c
@@ -32,7 +32,7 @@ static const WCHAR isPrototypeOfW[] = {'i','s','P','r','o','t','o','t','y','p','
 
 static const WCHAR default_valueW[] = {'[','o','b','j','e','c','t',' ','O','b','j','e','c','t',']',0};
 
-static HRESULT Object_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *jsdisp;
@@ -78,7 +78,7 @@ static HRESULT Object_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return S_OK;
 }
 
-static HRESULT Object_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -91,7 +91,7 @@ static HRESULT Object_toLocaleString(script_ctx_t *ctx, vdisp_t *jsthis, WORD fl
     return jsdisp_call_name(jsthis->u.jsdisp, toStringW, DISPATCH_METHOD, 0, NULL, r, ei);
 }
 
-static HRESULT Object_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -103,7 +103,7 @@ static HRESULT Object_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return S_OK;
 }
 
-static HRESULT Object_hasOwnProperty(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_hasOwnProperty(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR name;
@@ -118,7 +118,7 @@ static HRESULT Object_hasOwnProperty(script_ctx_t *ctx, vdisp_t *jsthis, WORD fl
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &name);
+    hres = to_string_jsval(ctx, argv[0], ei, &name);
     if(FAILED(hres))
         return hres;
 
@@ -147,21 +147,21 @@ static HRESULT Object_hasOwnProperty(script_ctx_t *ctx, vdisp_t *jsthis, WORD fl
     return S_OK;
 }
 
-static HRESULT Object_propertyIsEnumerable(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_propertyIsEnumerable(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT Object_isPrototypeOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_isPrototypeOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT Object_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT Object_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -215,7 +215,7 @@ static const builtin_info_t ObjectInst_info = {
     NULL
 };
 
-static HRESULT ObjectConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT ObjectConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     HRESULT hres;
@@ -225,10 +225,10 @@ static HRESULT ObjectConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     switch(flags) {
     case DISPATCH_METHOD:
         if(argc) {
-            if(V_VT(argv) != VT_EMPTY && V_VT(argv) != VT_NULL && (V_VT(argv) != VT_DISPATCH || V_DISPATCH(argv))) {
+            if(!is_undefined(argv[0]) && !is_null(argv[0]) && (!is_object_instance(argv[0]) || get_object(argv[0]))) {
                 IDispatch *disp;
 
-                hres = to_object(ctx, argv, &disp);
+                hres = to_object_jsval(ctx, argv[0], &disp);
                 if(FAILED(hres))
                     return hres;
 
diff --git a/dlls/jscript/regexp.c b/dlls/jscript/regexp.c
index 8a55d7e83bb..e783c540a15 100644
--- a/dlls/jscript/regexp.c
+++ b/dlls/jscript/regexp.c
@@ -3473,7 +3473,7 @@ HRESULT regexp_match(script_ctx_t *ctx, jsdisp_t *dispex, const WCHAR *str, DWOR
     return S_OK;
 }
 
-static HRESULT RegExp_source(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_source(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -3495,35 +3495,35 @@ static HRESULT RegExp_source(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return S_OK;
 }
 
-static HRESULT RegExp_global(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_global(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT RegExp_ignoreCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_ignoreCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT RegExp_multiline(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_multiline(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static INT index_from_var(script_ctx_t *ctx, VARIANT *v)
+static INT index_from_val(script_ctx_t *ctx, jsval_t v)
 {
     jsexcept_t ei;
     double n;
     HRESULT hres;
 
     memset(&ei, 0, sizeof(ei));
-    hres = to_number(ctx, v, &ei, &n);
+    hres = to_number_jsval(ctx, v, &ei, &n);
     if(FAILED(hres)) { /* FIXME: Move ignoring exceptions to to_primitive */
         VariantClear(&ei.var);
         return 0;
@@ -3533,7 +3533,7 @@ static INT index_from_var(script_ctx_t *ctx, VARIANT *v)
     return is_int32(n) ? n : 0;
 }
 
-static HRESULT RegExp_lastIndex(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_lastIndex(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -3548,11 +3548,11 @@ static HRESULT RegExp_lastIndex(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
         RegExpInstance *regexp = regexp_from_vdisp(jsthis);
         HRESULT hres;
 
-        hres = VariantCopy(&regexp->last_index_var, argv);
+        hres = jsval_to_variant(argv[0], &regexp->last_index_var);
         if(FAILED(hres))
             return hres;
 
-        regexp->last_index = index_from_var(ctx, argv);
+        regexp->last_index = index_from_val(ctx, argv[0]);
         break;
     }
     default:
@@ -3563,7 +3563,7 @@ static HRESULT RegExp_lastIndex(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return S_OK;
 }
 
-static HRESULT RegExp_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
@@ -3574,7 +3574,7 @@ static HRESULT create_match_array(script_ctx_t *ctx, BSTR input, const match_res
         const match_result_t *parens, DWORD parens_cnt, jsexcept_t *ei, IDispatch **ret)
 {
     jsdisp_t *array;
-    VARIANT var;
+    BSTR str;
     int i;
     HRESULT hres = S_OK;
 
@@ -3588,43 +3588,38 @@ static HRESULT create_match_array(script_ctx_t *ctx, BSTR input, const match_res
         return hres;
 
     for(i=0; i < parens_cnt; i++) {
-        V_VT(&var) = VT_BSTR;
-        V_BSTR(&var) = SysAllocStringLen(parens[i].str, parens[i].len);
-        if(!V_BSTR(&var)) {
+        str = SysAllocStringLen(parens[i].str, parens[i].len);
+        if(!str) {
             hres = E_OUTOFMEMORY;
             break;
         }
 
-        hres = jsdisp_propput_idx(array, i+1, &var, ei);
-        SysFreeString(V_BSTR(&var));
+        hres = jsdisp_propput_idx(array, i+1, jsval_string(str), ei);
+        SysFreeString(str);
         if(FAILED(hres))
             break;
     }
 
     while(SUCCEEDED(hres)) {
-        num_set_int(&var, result->str-input);
-        hres = jsdisp_propput_name(array, indexW, &var, ei);
+        hres = jsdisp_propput_name(array, indexW, jsval_number(result->str-input), ei);
         if(FAILED(hres))
             break;
 
-        num_set_int(&var, result->str-input+result->len);
-        hres = jsdisp_propput_name(array, lastIndexW, &var, ei);
+        hres = jsdisp_propput_name(array, lastIndexW, jsval_number(result->str-input+result->len), ei);
         if(FAILED(hres))
             break;
 
-        V_VT(&var) = VT_BSTR;
-        V_BSTR(&var) = input;
-        hres = jsdisp_propput_name(array, inputW, &var, ei);
+        hres = jsdisp_propput_name(array, inputW, jsval_string(input), ei);
         if(FAILED(hres))
             break;
 
-        V_BSTR(&var) = SysAllocStringLen(result->str, result->len);
-        if(!V_BSTR(&var)) {
+        str = SysAllocStringLen(result->str, result->len);
+        if(!str) {
             hres = E_OUTOFMEMORY;
             break;
         }
-        hres = jsdisp_propput_name(array, zeroW, &var, ei);
-        SysFreeString(V_BSTR(&var));
+        hres = jsdisp_propput_name(array, zeroW, jsval_string(str), ei);
+        SysFreeString(str);
         break;
     }
 
@@ -3637,7 +3632,7 @@ static HRESULT create_match_array(script_ctx_t *ctx, BSTR input, const match_res
     return S_OK;
 }
 
-static HRESULT run_exec(script_ctx_t *ctx, vdisp_t *jsthis, VARIANT *arg, jsexcept_t *ei, BSTR *input,
+static HRESULT run_exec(script_ctx_t *ctx, vdisp_t *jsthis, jsval_t arg, jsexcept_t *ei, BSTR *input,
         match_result_t *match, match_result_t **parens, DWORD *parens_cnt, VARIANT_BOOL *ret)
 {
     RegExpInstance *regexp;
@@ -3653,15 +3648,10 @@ static HRESULT run_exec(script_ctx_t *ctx, vdisp_t *jsthis, VARIANT *arg, jsexce
 
     regexp = regexp_from_vdisp(jsthis);
 
-    if(arg) {
-        hres = to_string(ctx, arg, ei, &string);
-        if(FAILED(hres))
-            return hres;
-        length = SysStringLen(string);
-    }else {
-        string = NULL;
-        length = 0;
-    }
+    hres = to_string_jsval(ctx, arg, ei, &string);
+    if(FAILED(hres))
+        return hres;
+    length = SysStringLen(string);
 
     if(regexp->jsregexp->flags & JSREG_GLOB) {
         if(regexp->last_index < 0) {
@@ -3694,7 +3684,7 @@ static HRESULT run_exec(script_ctx_t *ctx, vdisp_t *jsthis, VARIANT *arg, jsexce
     return S_OK;
 }
 
-static HRESULT RegExp_exec(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_exec(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     match_result_t *parens = NULL, match;
@@ -3705,7 +3695,7 @@ static HRESULT RegExp_exec(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
 
     TRACE("\n");
 
-    hres = run_exec(ctx, jsthis, argc ? argv : NULL, ei, &string, &match, &parens, &parens_cnt, &b);
+    hres = run_exec(ctx, jsthis, argc ? argv[0] : jsval_string(NULL), ei, &string, &match, &parens, &parens_cnt, &b);
     if(FAILED(hres))
         return hres;
 
@@ -3726,26 +3716,25 @@ static HRESULT RegExp_exec(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
     return hres;
 }
 
-static HRESULT RegExp_test(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_test(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     match_result_t match;
-    VARIANT undef_var;
+    BSTR undef_str;
     VARIANT_BOOL b;
     HRESULT hres;
 
     TRACE("\n");
 
     if(!argc) {
-        V_VT(&undef_var) = VT_BSTR;
-        V_BSTR(&undef_var) = SysAllocString(undefinedW);
-        if(!V_BSTR(&undef_var))
+        undef_str = SysAllocString(undefinedW);
+        if(!undef_str)
             return E_OUTOFMEMORY;
     }
 
-    hres = run_exec(ctx, jsthis, argc ? argv : &undef_var, ei, NULL, &match, NULL, NULL, &b);
+    hres = run_exec(ctx, jsthis, argc ? argv[0] : jsval_string(undef_str), ei, NULL, &match, NULL, NULL, &b);
     if(!argc)
-        SysFreeString(V_BSTR(&undef_var));
+        SysFreeString(undef_str);
     if(FAILED(hres))
         return hres;
 
@@ -3754,7 +3743,7 @@ static HRESULT RegExp_test(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
     return S_OK;
 }
 
-static HRESULT RegExp_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExp_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -3874,16 +3863,16 @@ HRESULT create_regexp(script_ctx_t *ctx, const WCHAR *exp, int len, DWORD flags,
     return S_OK;
 }
 
-HRESULT create_regexp_var(script_ctx_t *ctx, VARIANT *src_arg, VARIANT *flags_arg, jsdisp_t **ret)
+HRESULT create_regexp_var(script_ctx_t *ctx, jsval_t src_arg, jsval_t *flags_arg, jsdisp_t **ret)
 {
     const WCHAR *opt = emptyW, *src;
     DWORD flags;
     HRESULT hres;
 
-    if(V_VT(src_arg) == VT_DISPATCH) {
+    if(is_object_instance(src_arg)) {
         jsdisp_t *obj;
 
-        obj = iface_to_jsdisp((IUnknown*)V_DISPATCH(src_arg));
+        obj = iface_to_jsdisp((IUnknown*)get_object(src_arg));
         if(obj) {
             if(is_class(obj, JSCLASS_REGEXP)) {
                 RegExpInstance *regexp = (RegExpInstance*)obj;
@@ -3897,20 +3886,20 @@ HRESULT create_regexp_var(script_ctx_t *ctx, VARIANT *src_arg, VARIANT *flags_ar
         }
     }
 
-    if(V_VT(src_arg) != VT_BSTR) {
-        FIXME("flags_arg = %s\n", debugstr_variant(flags_arg));
+    if(!is_string(src_arg)) {
+        FIXME("src_arg = %s\n", debugstr_jsval(src_arg));
         return E_NOTIMPL;
     }
 
-    src = V_BSTR(src_arg);
+    src = get_string(src_arg);
 
     if(flags_arg) {
-        if(V_VT(flags_arg) != VT_BSTR) {
-            FIXME("unimplemented for vt %d\n", V_VT(flags_arg));
+        if(!is_string(*flags_arg)) {
+            FIXME("unimplemented for %s\n", debugstr_jsval(*flags_arg));
             return E_NOTIMPL;
         }
 
-        opt = V_BSTR(flags_arg);
+        opt = get_string(*flags_arg);
     }
 
     hres = parse_regexp_flags(opt, strlenW(opt), &flags);
@@ -3931,7 +3920,6 @@ HRESULT regexp_string_match(script_ctx_t *ctx, jsdisp_t *re, BSTR str,
     match_result_t *match_result;
     DWORD match_cnt, i, length;
     jsdisp_t *array;
-    VARIANT var;
     HRESULT hres;
 
     length = SysStringLen(str);
@@ -3977,35 +3965,32 @@ HRESULT regexp_string_match(script_ctx_t *ctx, jsdisp_t *re, BSTR str,
     if(FAILED(hres))
         return hres;
 
-    V_VT(&var) = VT_BSTR;
-
     for(i=0; i < match_cnt; i++) {
-        V_BSTR(&var) = SysAllocStringLen(match_result[i].str, match_result[i].len);
-        if(!V_BSTR(&var)) {
+        BSTR tmp_str;
+
+        tmp_str = SysAllocStringLen(match_result[i].str, match_result[i].len);
+        if(!tmp_str) {
             hres = E_OUTOFMEMORY;
             break;
         }
 
-        hres = jsdisp_propput_idx(array, i, &var, ei);
-        SysFreeString(V_BSTR(&var));
+        hres = jsdisp_propput_idx(array, i, jsval_string(tmp_str), ei);
+        SysFreeString(tmp_str);
         if(FAILED(hres))
             break;
     }
 
     while(SUCCEEDED(hres)) {
-        num_set_int(&var, match_result[match_cnt-1].str-str);
-        hres = jsdisp_propput_name(array, indexW, &var, ei);
+        hres = jsdisp_propput_name(array, indexW, jsval_number(match_result[match_cnt-1].str-str), ei);
         if(FAILED(hres))
             break;
 
-        num_set_int(&var, match_result[match_cnt-1].str-str+match_result[match_cnt-1].len);
-        hres = jsdisp_propput_name(array, lastIndexW, &var, ei);
+        hres = jsdisp_propput_name(array, lastIndexW,
+                jsval_number(match_result[match_cnt-1].str-str+match_result[match_cnt-1].len), ei);
         if(FAILED(hres))
             break;
 
-        V_VT(&var) = VT_BSTR;
-        V_BSTR(&var) = str;
-        hres = jsdisp_propput_name(array, inputW, &var, ei);
+        hres = jsdisp_propput_name(array, inputW, jsval_string(str), ei);
         break;
     }
 
@@ -4019,7 +4004,7 @@ HRESULT regexp_string_match(script_ctx_t *ctx, jsdisp_t *re, BSTR str,
 }
 
 static HRESULT RegExpConstr_leftContext(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-         unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+         unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
 
@@ -4045,7 +4030,7 @@ static HRESULT RegExpConstr_leftContext(script_ctx_t *ctx, vdisp_t *jsthis, WORD
 }
 
 static HRESULT RegExpConstr_rightContext(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-         unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+         unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
 
@@ -4070,7 +4055,7 @@ static HRESULT RegExpConstr_rightContext(script_ctx_t *ctx, vdisp_t *jsthis, WOR
     return S_OK;
 }
 
-static HRESULT RegExpConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT RegExpConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -4078,11 +4063,11 @@ static HRESULT RegExpConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     switch(flags) {
     case DISPATCH_METHOD:
         if(argc) {
-            if(V_VT(argv) == VT_DISPATCH) {
-                jsdisp_t *jsdisp = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv));
+            if(is_object_instance(argv[0])) {
+                jsdisp_t *jsdisp = iface_to_jsdisp((IUnknown*)get_object(argv[0]));
                 if(jsdisp) {
                     if(is_class(jsdisp, JSCLASS_REGEXP)) {
-                        if(argc > 1 && V_VT(argv+1) != VT_EMPTY) {
+                        if(argc > 1 && !is_undefined(argv[1])) {
                             jsdisp_release(jsdisp);
                             return throw_regexp_error(ctx, ei, JS_E_REGEXP_SYNTAX, NULL);
                         }
@@ -4107,7 +4092,7 @@ static HRESULT RegExpConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
             return E_NOTIMPL;
         }
 
-        hres = create_regexp_var(ctx, argv, argc > 1 ? argv+1 : NULL, &ret);
+        hres = create_regexp_var(ctx, argv[0], argc > 1 ? argv+1 : NULL, &ret);
         if(FAILED(hres))
             return hres;
 
diff --git a/dlls/jscript/string.c b/dlls/jscript/string.c
index 89d7aee1e48..1549ca1bf25 100644
--- a/dlls/jscript/string.c
+++ b/dlls/jscript/string.c
@@ -102,7 +102,7 @@ static HRESULT get_string_val(script_ctx_t *ctx, vdisp_t *jsthis, jsexcept_t *ei
     return S_OK;
 }
 
-static HRESULT String_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_length(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("%p\n", jsthis);
@@ -142,7 +142,7 @@ static HRESULT stringobj_to_string(vdisp_t *jsthis, jsval_t *r)
 }
 
 /* ECMA-262 3rd Edition    15.5.4.2 */
-static HRESULT String_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -151,7 +151,7 @@ static HRESULT String_toString(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
 }
 
 /* ECMA-262 3rd Edition    15.5.4.2 */
-static HRESULT String_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_valueOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     TRACE("\n");
@@ -188,7 +188,7 @@ static HRESULT do_attributeless_tag_format(script_ctx_t *ctx, vdisp_t *jsthis, j
     return S_OK;
 }
 
-static HRESULT do_attribute_tag_format(script_ctx_t *ctx, vdisp_t *jsthis, unsigned argc, VARIANT *argv, jsval_t *r,
+static HRESULT do_attribute_tag_format(script_ctx_t *ctx, vdisp_t *jsthis, unsigned argc, jsval_t *argv, jsval_t *r,
         jsexcept_t *ei, const WCHAR *tagname, const WCHAR *attr)
 {
     static const WCHAR tagfmtW[]
@@ -220,7 +220,7 @@ static HRESULT do_attribute_tag_format(script_ctx_t *ctx, vdisp_t *jsthis, unsig
     }
 
     if(argc) {
-        hres = to_string(ctx, argv, ei, &attr_value);
+        hres = to_string_jsval(ctx, argv[0], ei, &attr_value);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -252,7 +252,7 @@ static HRESULT do_attribute_tag_format(script_ctx_t *ctx, vdisp_t *jsthis, unsig
     return S_OK;
 }
 
-static HRESULT String_anchor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_anchor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR fontW[] = {'A',0};
@@ -261,21 +261,21 @@ static HRESULT String_anchor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return do_attribute_tag_format(ctx, jsthis, argc, argv, r, ei, fontW, colorW);
 }
 
-static HRESULT String_big(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_big(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR bigtagW[] = {'B','I','G',0};
     return do_attributeless_tag_format(ctx, jsthis, r, ei, bigtagW);
 }
 
-static HRESULT String_blink(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_blink(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR blinktagW[] = {'B','L','I','N','K',0};
     return do_attributeless_tag_format(ctx, jsthis, r, ei, blinktagW);
 }
 
-static HRESULT String_bold(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_bold(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR boldtagW[] = {'B',0};
@@ -283,7 +283,7 @@ static HRESULT String_bold(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
 }
 
 /* ECMA-262 3rd Edition    15.5.4.5 */
-static HRESULT String_charAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_charAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR *str;
@@ -301,7 +301,7 @@ static HRESULT String_charAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     if(argc) {
         double d;
 
-        hres = to_integer(ctx, argv, ei, &d);
+        hres = to_integer(ctx, argv[0], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -328,7 +328,7 @@ static HRESULT String_charAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.5.4.5 */
-static HRESULT String_charCodeAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_charCodeAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR *str;
@@ -345,7 +345,7 @@ static HRESULT String_charCodeAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     if(argc > 0) {
         double d;
 
-        hres = to_integer(ctx, argv, ei, &d);
+        hres = to_integer(ctx, argv[0], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -369,7 +369,7 @@ static HRESULT String_charCodeAt(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    15.5.4.6 */
-static HRESULT String_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR *strs = NULL, ret = NULL;
@@ -391,7 +391,7 @@ static HRESULT String_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     hres = to_string(ctx, &var, ei, strs);
     if(SUCCEEDED(hres)) {
         for(i=0; i < argc; i++) {
-            hres = to_string(ctx, argv+i, ei, strs+i+1);
+            hres = to_string_jsval(ctx, argv[i], ei, strs+i+1);
             if(FAILED(hres))
                 break;
         }
@@ -424,14 +424,14 @@ static HRESULT String_concat(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return S_OK;
 }
 
-static HRESULT String_fixed(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_fixed(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR fixedtagW[] = {'T','T',0};
     return do_attributeless_tag_format(ctx, jsthis, r, ei, fixedtagW);
 }
 
-static HRESULT String_fontcolor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_fontcolor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR fontW[] = {'F','O','N','T',0};
@@ -440,7 +440,7 @@ static HRESULT String_fontcolor(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     return do_attribute_tag_format(ctx, jsthis, argc, argv, r, ei, fontW, colorW);
 }
 
-static HRESULT String_fontsize(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_fontsize(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR fontW[] = {'F','O','N','T',0};
@@ -449,7 +449,7 @@ static HRESULT String_fontsize(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, u
     return do_attribute_tag_format(ctx, jsthis, argc, argv, r, ei, fontW, colorW);
 }
 
-static HRESULT String_indexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_indexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     DWORD length, pos = 0;
@@ -471,7 +471,7 @@ static HRESULT String_indexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &search_str);
+    hres = to_string_jsval(ctx, argv[0], ei, &search_str);
     if(FAILED(hres)) {
         SysFreeString(val_str);
         return hres;
@@ -480,7 +480,7 @@ static HRESULT String_indexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     if(argc >= 2) {
         double d;
 
-        hres = to_integer(ctx, argv+1, ei, &d);
+        hres = to_integer(ctx, argv[1], ei, &d);
         if(SUCCEEDED(hres) && d > 0.0)
             pos = is_int32(d) ? min(length, d) : length;
     }
@@ -505,7 +505,7 @@ static HRESULT String_indexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return S_OK;
 }
 
-static HRESULT String_italics(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_italics(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR italicstagW[] = {'I',0};
@@ -513,7 +513,7 @@ static HRESULT String_italics(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
 }
 
 /* ECMA-262 3rd Edition    15.5.4.8 */
-static HRESULT String_lastIndexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_lastIndexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR search_str, val_str;
@@ -535,7 +535,7 @@ static HRESULT String_lastIndexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         return S_OK;
     }
 
-    hres = to_string(ctx, argv, ei, &search_str);
+    hres = to_string_jsval(ctx, argv[0], ei, &search_str);
     if(FAILED(hres)) {
         SysFreeString(val_str);
         return hres;
@@ -546,7 +546,7 @@ static HRESULT String_lastIndexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     if(argc >= 2) {
         double d;
 
-        hres = to_integer(ctx, argv+1, ei, &d);
+        hres = to_integer(ctx, argv[1], ei, &d);
         if(SUCCEEDED(hres) && d > 0)
             pos = is_int32(d) ? min(length, d) : length;
     }else {
@@ -574,7 +574,7 @@ static HRESULT String_lastIndexOf(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return S_OK;
 }
 
-static HRESULT String_link(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_link(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR fontW[] = {'A',0};
@@ -584,11 +584,11 @@ static HRESULT String_link(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsig
 }
 
 /* ECMA-262 3rd Edition    15.5.4.10 */
-static HRESULT String_match(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_match(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
+    jsdisp_t *regexp = NULL;
     const WCHAR *str;
-    jsdisp_t *regexp;
     DWORD length;
     BSTR val_str = NULL;
     HRESULT hres = S_OK;
@@ -601,18 +601,18 @@ static HRESULT String_match(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
         return S_OK;
     }
 
-    switch(V_VT(argv)) {
-    case VT_DISPATCH:
-        regexp = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv));
-        if(regexp) {
-            if(is_class(regexp, JSCLASS_REGEXP))
-                break;
+    if(is_object_instance(argv[0])) {
+        regexp = iface_to_jsdisp((IUnknown*)get_object(argv[0]));
+        if(regexp && !is_class(regexp, JSCLASS_REGEXP)) {
             jsdisp_release(regexp);
+            regexp = NULL;
         }
-    default: {
+    }
+
+    if(!regexp) {
         BSTR match_str;
 
-        hres = to_string(ctx, argv, ei, &match_str);
+        hres = to_string_jsval(ctx, argv[0], ei, &match_str);
         if(FAILED(hres))
             return hres;
 
@@ -621,7 +621,6 @@ static HRESULT String_match(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
         if(FAILED(hres))
             return hres;
     }
-    }
 
     hres = get_string_val(ctx, jsthis, ei, &str, &length, &val_str);
     if(SUCCEEDED(hres)) {
@@ -675,40 +674,41 @@ static HRESULT strbuf_append(strbuf_t *buf, const WCHAR *str, DWORD len)
 static HRESULT rep_call(script_ctx_t *ctx, jsdisp_t *func, const WCHAR *str, match_result_t *match,
         match_result_t *parens, DWORD parens_cnt, BSTR *ret, jsexcept_t *ei)
 {
-    VARIANT *argv;
+    jsval_t *argv;
     unsigned argc;
     jsval_t val;
+    BSTR tmp_str;
     DWORD i;
     HRESULT hres = S_OK;
 
     argc = parens_cnt+3;
-    argv = heap_alloc_zero(sizeof(VARIANT)*argc);
+    argv = heap_alloc_zero(sizeof(*argv)*argc);
     if(!argv)
         return E_OUTOFMEMORY;
 
-    V_VT(argv) = VT_BSTR;
-    V_BSTR(argv) = SysAllocStringLen(match->str, match->len);
-    if(!V_BSTR(argv))
+    tmp_str = SysAllocStringLen(match->str, match->len);
+    if(!tmp_str)
         hres = E_OUTOFMEMORY;
+    argv[0] = jsval_string(tmp_str);
 
     if(SUCCEEDED(hres)) {
         for(i=0; i < parens_cnt; i++) {
-            V_VT(argv+i+1) = VT_BSTR;
-            V_BSTR(argv+i+1) = SysAllocStringLen(parens[i].str, parens[i].len);
-            if(!V_BSTR(argv+i+1)) {
+            tmp_str = SysAllocStringLen(parens[i].str, parens[i].len);
+            if(!tmp_str) {
                hres = E_OUTOFMEMORY;
                break;
             }
+            argv[i+1] = jsval_string(tmp_str);
         }
     }
 
     if(SUCCEEDED(hres)) {
-        num_set_int(argv+parens_cnt+1, match->str - str);
+        argv[parens_cnt+1] = jsval_number(match->str - str);
 
-        V_VT(argv+parens_cnt+2) = VT_BSTR;
-        V_BSTR(argv+parens_cnt+2) = SysAllocString(str);
-        if(!V_BSTR(argv+parens_cnt+2))
+        tmp_str = SysAllocString(str);
+        if(!tmp_str)
             hres = E_OUTOFMEMORY;
+        argv[parens_cnt+2] = jsval_string(tmp_str);
     }
 
     if(SUCCEEDED(hres))
@@ -716,7 +716,7 @@ static HRESULT rep_call(script_ctx_t *ctx, jsdisp_t *func, const WCHAR *str, mat
 
     for(i=0; i < parens_cnt+3; i++) {
         if(i != parens_cnt+1)
-            SysFreeString(V_BSTR(argv+i));
+            SysFreeString(get_string(argv[i]));
     }
     heap_free(argv);
 
@@ -729,7 +729,7 @@ static HRESULT rep_call(script_ctx_t *ctx, jsdisp_t *func, const WCHAR *str, mat
 }
 
 /* ECMA-262 3rd Edition    15.5.4.11 */
-static HRESULT String_replace(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_replace(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR *str;
@@ -760,20 +760,16 @@ static HRESULT String_replace(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
         return S_OK;
     }
 
-    switch(V_VT(argv)) {
-    case VT_DISPATCH:
-        regexp = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv));
-        if(regexp) {
-            if(is_class(regexp, JSCLASS_REGEXP)) {
-                break;
-            }else {
-                jsdisp_release(regexp);
-                regexp = NULL;
-            }
+    if(is_object_instance(argv[0])) {
+        regexp = iface_to_jsdisp((IUnknown*)get_object(argv[0]));
+        if(regexp && !is_class(regexp, JSCLASS_REGEXP)) {
+            jsdisp_release(regexp);
+            regexp = NULL;
         }
+    }
 
-    default:
-        hres = to_string(ctx, argv, ei, &match_str);
+    if(!regexp) {
+        hres = to_string_jsval(ctx, argv[0], ei, &match_str);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -781,26 +777,21 @@ static HRESULT String_replace(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     }
 
     if(argc >= 2) {
-        switch(V_VT(argv+1)) {
-        case VT_DISPATCH:
-            rep_func = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv+1));
-            if(rep_func) {
-                if(is_class(rep_func, JSCLASS_FUNCTION)) {
-                    break;
-                }else {
-                    jsdisp_release(rep_func);
-                    rep_func = NULL;
-                }
+        if(is_object_instance(argv[1])) {
+            rep_func = iface_to_jsdisp((IUnknown*)get_object(argv[1]));
+            if(rep_func && !is_class(rep_func, JSCLASS_FUNCTION)) {
+                jsdisp_release(rep_func);
+                rep_func = NULL;
             }
+        }
 
-        default:
-            hres = to_string(ctx, argv+1, ei, &rep_str);
-            if(FAILED(hres))
-                break;
-
-            rep_len = SysStringLen(rep_str);
-            if(!strchrW(rep_str, '$'))
-                parens_ptr = NULL;
+        if(!rep_func) {
+            hres = to_string_jsval(ctx, argv[1], ei, &rep_str);
+            if(SUCCEEDED(hres)) {
+                rep_len = SysStringLen(rep_str);
+                if(!strchrW(rep_str, '$'))
+                    parens_ptr = NULL;
+            }
         }
     }
 
@@ -963,7 +954,7 @@ static HRESULT String_replace(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, un
     return hres;
 }
 
-static HRESULT String_search(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_search(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     jsdisp_t *regexp = NULL;
@@ -986,18 +977,16 @@ static HRESULT String_search(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
         return S_OK;
     }
 
-    if(V_VT(argv) == VT_DISPATCH) {
-        regexp = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv));
-        if(regexp) {
-            if(!is_class(regexp, JSCLASS_REGEXP)) {
-                jsdisp_release(regexp);
-                regexp = NULL;
-            }
+    if(is_object_instance(argv[0])) {
+        regexp = iface_to_jsdisp((IUnknown*)get_object(argv[0]));
+        if(regexp && !is_class(regexp, JSCLASS_REGEXP)) {
+            jsdisp_release(regexp);
+            regexp = NULL;
         }
     }
 
     if(!regexp) {
-        hres = create_regexp_var(ctx, argv, NULL, &regexp);
+        hres = create_regexp_var(ctx, argv[0], NULL, &regexp);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1017,7 +1006,7 @@ static HRESULT String_search(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
 }
 
 /* ECMA-262 3rd Edition    15.5.4.13 */
-static HRESULT String_slice(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_slice(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR *str;
@@ -1034,7 +1023,7 @@ static HRESULT String_slice(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
         return hres;
 
     if(argc) {
-        hres = to_integer(ctx, argv, ei, &d);
+        hres = to_integer(ctx, argv[0], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1055,7 +1044,7 @@ static HRESULT String_slice(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     }
 
     if(argc >= 2) {
-        hres = to_integer(ctx, argv+1, ei, &d);
+        hres = to_integer(ctx, argv[1], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1094,23 +1083,22 @@ static HRESULT String_slice(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     return S_OK;
 }
 
-static HRESULT String_small(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_small(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR smalltagW[] = {'S','M','A','L','L',0};
     return do_attributeless_tag_format(ctx, jsthis, r, ei, smalltagW);
 }
 
-static HRESULT String_split(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_split(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     match_result_t *match_result = NULL;
     DWORD length, match_cnt, i, match_len = 0;
     const WCHAR *str, *ptr, *ptr2;
     BOOL use_regexp = FALSE;
-    VARIANT var;
     jsdisp_t *array;
-    BSTR val_str, match_str = NULL;
+    BSTR val_str, match_str = NULL, tmp_str;
     HRESULT hres;
 
     TRACE("\n");
@@ -1124,27 +1112,25 @@ static HRESULT String_split(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     if(FAILED(hres))
         return hres;
 
-    switch(V_VT(argv)) {
-    case VT_DISPATCH: {
+    if(is_object_instance(argv[0])) {
         jsdisp_t *regexp;
 
-        regexp = iface_to_jsdisp((IUnknown*)V_DISPATCH(argv));
+        regexp = iface_to_jsdisp((IUnknown*)get_object(argv[0]));
         if(regexp) {
             if(is_class(regexp, JSCLASS_REGEXP)) {
                 use_regexp = TRUE;
                 hres = regexp_match(ctx, regexp, str, length, TRUE, &match_result, &match_cnt);
-                jsdisp_release(regexp);
-                if(FAILED(hres)) {
-                    SysFreeString(val_str);
-                    return hres;
-                }
-                break;
             }
             jsdisp_release(regexp);
+            if(FAILED(hres)) {
+                SysFreeString(val_str);
+                return hres;
+            }
         }
     }
-    default:
-        hres = to_string(ctx, argv, ei, &match_str);
+
+    if(!use_regexp) {
+        hres = to_string_jsval(ctx, argv[0], ei, &match_str);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1176,15 +1162,14 @@ static HRESULT String_split(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
                 ptr2 = ptr+1;
             }
 
-            V_VT(&var) = VT_BSTR;
-            V_BSTR(&var) = SysAllocStringLen(ptr, ptr2-ptr);
-            if(!V_BSTR(&var)) {
+            tmp_str = SysAllocStringLen(ptr, ptr2-ptr);
+            if(!tmp_str) {
                 hres = E_OUTOFMEMORY;
                 break;
             }
 
-            hres = jsdisp_propput_idx(array, i, &var, ei);
-            SysFreeString(V_BSTR(&var));
+            hres = jsdisp_propput_idx(array, i, jsval_string(tmp_str), ei);
+            SysFreeString(tmp_str);
             if(FAILED(hres))
                 break;
 
@@ -1201,12 +1186,11 @@ static HRESULT String_split(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
         DWORD len = (str+length) - ptr;
 
         if(len || match_str) {
-            V_VT(&var) = VT_BSTR;
-            V_BSTR(&var) = SysAllocStringLen(ptr, len);
+            tmp_str = SysAllocStringLen(ptr, len);
 
-            if(V_BSTR(&var)) {
-                hres = jsdisp_propput_idx(array, i, &var, ei);
-                SysFreeString(V_BSTR(&var));
+            if(tmp_str) {
+                hres = jsdisp_propput_idx(array, i, jsval_string(tmp_str), ei);
+                SysFreeString(tmp_str);
             }else {
                 hres = E_OUTOFMEMORY;
             }
@@ -1225,14 +1209,14 @@ static HRESULT String_split(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsi
     return hres;
 }
 
-static HRESULT String_strike(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_strike(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR striketagW[] = {'S','T','R','I','K','E',0};
     return do_attributeless_tag_format(ctx, jsthis, r, ei, striketagW);
 }
 
-static HRESULT String_sub(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_sub(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR subtagW[] = {'S','U','B',0};
@@ -1240,7 +1224,7 @@ static HRESULT String_sub(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsign
 }
 
 /* ECMA-262 3rd Edition    15.5.4.15 */
-static HRESULT String_substring(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_substring(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR *str;
@@ -1257,7 +1241,7 @@ static HRESULT String_substring(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
         return hres;
 
     if(argc >= 1) {
-        hres = to_integer(ctx, argv, ei, &d);
+        hres = to_integer(ctx, argv[0], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1268,7 +1252,7 @@ static HRESULT String_substring(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
     }
 
     if(argc >= 2) {
-        hres = to_integer(ctx, argv+1, ei, &d);
+        hres = to_integer(ctx, argv[1], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1301,7 +1285,7 @@ static HRESULT String_substring(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
 }
 
 /* ECMA-262 3rd Edition    B.2.3 */
-static HRESULT String_substr(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_substr(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     BSTR val_str;
@@ -1318,7 +1302,7 @@ static HRESULT String_substr(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
         return hres;
 
     if(argc >= 1) {
-        hres = to_integer(ctx, argv, ei, &d);
+        hres = to_integer(ctx, argv[0], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1329,7 +1313,7 @@ static HRESULT String_substr(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     }
 
     if(argc >= 2) {
-        hres = to_integer(ctx, argv+1, ei, &d);
+        hres = to_integer(ctx, argv[1], ei, &d);
         if(FAILED(hres)) {
             SysFreeString(val_str);
             return hres;
@@ -1356,14 +1340,14 @@ static HRESULT String_substr(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, uns
     return hres;
 }
 
-static HRESULT String_sup(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_sup(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     static const WCHAR suptagW[] = {'S','U','P',0};
     return do_attributeless_tag_format(ctx, jsthis, r, ei, suptagW);
 }
 
-static HRESULT String_toLowerCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_toLowerCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR* str;
@@ -1391,7 +1375,7 @@ static HRESULT String_toLowerCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return S_OK;
 }
 
-static HRESULT String_toUpperCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_toUpperCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     const WCHAR* str;
@@ -1419,28 +1403,28 @@ static HRESULT String_toUpperCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
     return S_OK;
 }
 
-static HRESULT String_toLocaleLowerCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_toLocaleLowerCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT String_toLocaleUpperCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_toLocaleUpperCase(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT String_localeCompare(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_localeCompare(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
     return E_NOTIMPL;
 }
 
-static HRESULT String_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT String_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     StringInstance *This = string_from_vdisp(jsthis);
@@ -1534,7 +1518,7 @@ static const builtin_info_t StringInst_info = {
 
 /* ECMA-262 3rd Edition    15.5.3.2 */
 static HRESULT StringConstr_fromCharCode(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags,
-        unsigned argc, VARIANT *argv, jsval_t *r, jsexcept_t *ei)
+        unsigned argc, jsval_t *argv, jsval_t *r, jsexcept_t *ei)
 {
     DWORD i, code;
     BSTR ret;
@@ -1547,7 +1531,7 @@ static HRESULT StringConstr_fromCharCode(script_ctx_t *ctx, vdisp_t *jsthis, WOR
         return E_OUTOFMEMORY;
 
     for(i=0; i<argc; i++) {
-        hres = to_uint32(ctx, argv+i, ei, &code);
+        hres = to_uint32_jsval(ctx, argv[i], ei, &code);
         if(FAILED(hres)) {
             SysFreeString(ret);
             return hres;
@@ -1563,7 +1547,7 @@ static HRESULT StringConstr_fromCharCode(script_ctx_t *ctx, vdisp_t *jsthis, WOR
     return S_OK;
 }
 
-static HRESULT StringConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT StringConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     HRESULT hres;
@@ -1575,7 +1559,7 @@ static HRESULT StringConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         BSTR str;
 
         if(argc) {
-            hres = to_string(ctx, argv, ei, &str);
+            hres = to_string_jsval(ctx, argv[0], ei, &str);
             if(FAILED(hres))
                 return hres;
         }else {
@@ -1593,7 +1577,7 @@ static HRESULT StringConstr_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags
         if(argc) {
             BSTR str;
 
-            hres = to_string(ctx, argv, ei, &str);
+            hres = to_string_jsval(ctx, argv[0], ei, &str);
             if(FAILED(hres))
                 return hres;
 
diff --git a/dlls/jscript/vbarray.c b/dlls/jscript/vbarray.c
index a6e7412fc52..fc22806a7b8 100644
--- a/dlls/jscript/vbarray.c
+++ b/dlls/jscript/vbarray.c
@@ -44,7 +44,7 @@ static inline VBArrayInstance *vbarray_this(vdisp_t *jsthis)
     return is_vclass(jsthis, JSCLASS_VBARRAY) ? vbarray_from_vdisp(jsthis) : NULL;
 }
 
-static HRESULT VBArray_dimensions(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArray_dimensions(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     VBArrayInstance *vbarray;
@@ -60,7 +60,7 @@ static HRESULT VBArray_dimensions(script_ctx_t *ctx, vdisp_t *vthis, WORD flags,
     return S_OK;
 }
 
-static HRESULT VBArray_getItem(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArray_getItem(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     VBArrayInstance *vbarray;
@@ -82,7 +82,7 @@ static HRESULT VBArray_getItem(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, un
         return E_OUTOFMEMORY;
 
     for(i=0; i<argc; i++) {
-        hres = to_int32(ctx, argv+i, ei, indexes+i);
+        hres = to_int32(ctx, argv[i], ei, indexes+i);
         if(FAILED(hres)) {
             heap_free(indexes);
             return hres;
@@ -96,12 +96,14 @@ static HRESULT VBArray_getItem(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, un
     else if(FAILED(hres))
         return hres;
 
-    if(r)
-        hres = jsval_variant(r, &out);
+    if(r) {
+        hres = variant_to_jsval(&out, r);
+        VariantClear(&out);
+    }
     return hres;
 }
 
-static HRESULT VBArray_lbound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArray_lbound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     VBArrayInstance *vbarray;
@@ -115,7 +117,7 @@ static HRESULT VBArray_lbound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, uns
         return throw_type_error(ctx, ei, JS_E_VBARRAY_EXPECTED, NULL);
 
     if(argc) {
-        hres = to_int32(ctx, argv, ei, &dim);
+        hres = to_int32(ctx, argv[0], ei, &dim);
         if(FAILED(hres))
             return hres;
     } else
@@ -132,11 +134,12 @@ static HRESULT VBArray_lbound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, uns
     return S_OK;
 }
 
-static HRESULT VBArray_toArray(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArray_toArray(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     VBArrayInstance *vbarray;
     jsdisp_t *array;
+    jsval_t val;
     VARIANT *v;
     int i, size = 1, ubound, lbound;
     HRESULT hres;
@@ -164,7 +167,11 @@ static HRESULT VBArray_toArray(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, un
     }
 
     for(i=0; i<size; i++) {
-        hres = jsdisp_propput_idx(array, i, v, ei);
+        hres = variant_to_jsval(v, &val);
+        if(SUCCEEDED(hres)) {
+            hres = jsdisp_propput_idx(array, i, val, ei);
+            jsval_release(val);
+        }
         if(FAILED(hres)) {
             SafeArrayUnaccessData(vbarray->safearray);
             jsdisp_release(array);
@@ -180,7 +187,7 @@ static HRESULT VBArray_toArray(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, un
     return S_OK;
 }
 
-static HRESULT VBArray_ubound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArray_ubound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     VBArrayInstance *vbarray;
@@ -194,7 +201,7 @@ static HRESULT VBArray_ubound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, uns
         return throw_type_error(ctx, ei, JS_E_VBARRAY_EXPECTED, NULL);
 
     if(argc) {
-        hres = to_int32(ctx, argv, ei, &dim);
+        hres = to_int32(ctx, argv[0], ei, &dim);
         if(FAILED(hres))
             return hres;
     } else
@@ -211,7 +218,7 @@ static HRESULT VBArray_ubound(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, uns
     return S_OK;
 }
 
-static HRESULT VBArray_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArray_value(script_ctx_t *ctx, vdisp_t *jsthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     FIXME("\n");
@@ -273,7 +280,7 @@ static HRESULT alloc_vbarray(script_ctx_t *ctx, jsdisp_t *object_prototype, VBAr
     return S_OK;
 }
 
-static HRESULT VBArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, VARIANT *argv,
+static HRESULT VBArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags, unsigned argc, jsval_t *argv,
         jsval_t *r, jsexcept_t *ei)
 {
     VBArrayInstance *vbarray;
@@ -283,20 +290,20 @@ static HRESULT VBArrayConstr_value(script_ctx_t *ctx, vdisp_t *vthis, WORD flags
 
     switch(flags) {
     case DISPATCH_METHOD:
-        if(argc<1 || V_VT(argv) != (VT_ARRAY|VT_VARIANT))
+        if(argc<1 || !is_variant(argv[0]) || V_VT(get_variant(argv[0])) != (VT_ARRAY|VT_VARIANT))
             return throw_type_error(ctx, ei, JS_E_VBARRAY_EXPECTED, NULL);
 
-        return variant_to_jsval(argv, r);
+        return jsval_copy(argv[0], r);
 
     case DISPATCH_CONSTRUCT:
-        if(argc<1 || V_VT(argv) != (VT_ARRAY|VT_VARIANT))
+        if(argc<1 || !is_variant(argv[0]) || V_VT(get_variant(argv[0])) != (VT_ARRAY|VT_VARIANT))
             return throw_type_error(ctx, ei, JS_E_VBARRAY_EXPECTED, NULL);
 
         hres = alloc_vbarray(ctx, NULL, &vbarray);
         if(FAILED(hres))
             return hres;
 
-        hres = SafeArrayCopy(V_ARRAY(argv), &vbarray->safearray);
+        hres = SafeArrayCopy(V_ARRAY(get_variant(argv[0])), &vbarray->safearray);
         if(FAILED(hres)) {
             jsdisp_release(&vbarray->dispex);
             return hres;