diff --git a/dlls/jscript/dispex.c b/dlls/jscript/dispex.c
index 6894eae0515..07880bcff5b 100644
--- a/dlls/jscript/dispex.c
+++ b/dlls/jscript/dispex.c
@@ -358,6 +358,9 @@ static HRESULT prop_put(DispatchEx *This, dispex_prop_t *prop, VARIANT *val,
 {
     HRESULT hres;
 
+    if(prop->flags & PROPF_CONST)
+        return S_OK;
+
     switch(prop->type) {
     case PROP_BUILTIN:
         if(!(prop->flags & PROPF_METHOD)) {
@@ -974,6 +977,18 @@ HRESULT jsdisp_propput_name(DispatchEx *obj, const WCHAR *name, VARIANT *val, js
     return prop_put(obj, prop, val, ei, caller);
 }
 
+HRESULT jsdisp_propput_const(DispatchEx *obj, const WCHAR *name, VARIANT *val)
+{
+    dispex_prop_t *prop;
+    HRESULT hres;
+
+    hres = ensure_prop_name(obj, name, FALSE, PROPF_ENUM|PROPF_CONST, &prop);
+    if(FAILED(hres))
+        return hres;
+
+    return VariantCopy(&prop->u.var, val);
+}
+
 HRESULT jsdisp_propput_idx(DispatchEx *obj, DWORD idx, VARIANT *val, jsexcept_t *ei, IServiceProvider *caller)
 {
     WCHAR buf[12];
diff --git a/dlls/jscript/function.c b/dlls/jscript/function.c
index c7494cfce6c..df46f1d996d 100644
--- a/dlls/jscript/function.c
+++ b/dlls/jscript/function.c
@@ -606,7 +606,16 @@ HRESULT create_builtin_function(script_ctx_t *ctx, builtin_invoke_t value_proc,
     if(FAILED(hres))
         return hres;
 
-    hres = set_prototype(ctx, &function->dispex, prototype);
+    if(builtin_info) {
+        VARIANT var;
+
+        V_VT(&var) = VT_I4;
+        V_I4(&var) = function->length;
+        hres = jsdisp_propput_const(&function->dispex, lengthW, &var);
+    }
+
+    if(SUCCEEDED(hres))
+        hres = set_prototype(ctx, &function->dispex, prototype);
     if(FAILED(hres)) {
         jsdisp_release(&function->dispex);
         return hres;
diff --git a/dlls/jscript/jscript.h b/dlls/jscript/jscript.h
index c1c8e60f35b..c58c05dc1d0 100644
--- a/dlls/jscript/jscript.h
+++ b/dlls/jscript/jscript.h
@@ -68,6 +68,7 @@ extern HINSTANCE jscript_hinstance;
 #define PROPF_METHOD  0x0100
 #define PROPF_ENUM    0x0200
 #define PROPF_CONSTR  0x0400
+#define PROPF_CONST   0x0800
 
 /* NOTE: Keep in sync with names in Object.toString implementation */
 typedef enum {
@@ -203,6 +204,7 @@ HRESULT disp_propget(script_ctx_t*,IDispatch*,DISPID,VARIANT*,jsexcept_t*,IServi
 HRESULT disp_propput(script_ctx_t*,IDispatch*,DISPID,VARIANT*,jsexcept_t*,IServiceProvider*);
 HRESULT jsdisp_propget(DispatchEx*,DISPID,VARIANT*,jsexcept_t*,IServiceProvider*);
 HRESULT jsdisp_propput_name(DispatchEx*,const WCHAR*,VARIANT*,jsexcept_t*,IServiceProvider*);
+HRESULT jsdisp_propput_const(DispatchEx*,const WCHAR*,VARIANT*);
 HRESULT jsdisp_propput_idx(DispatchEx*,DWORD,VARIANT*,jsexcept_t*,IServiceProvider*);
 HRESULT jsdisp_propget_name(DispatchEx*,LPCWSTR,VARIANT*,jsexcept_t*,IServiceProvider*);
 HRESULT jsdisp_get_idx(DispatchEx*,DWORD,VARIANT*,jsexcept_t*,IServiceProvider*);
@@ -318,8 +320,9 @@ typedef struct {
     DWORD len;
 } match_result_t;
 
-#define REM_CHECK_GLOBAL 0x0001
-#define REM_RESET_INDEX  0x0002
+#define REM_CHECK_GLOBAL   0x0001
+#define REM_RESET_INDEX    0x0002
+#define REM_NO_CTX_UPDATE  0x0004
 HRESULT regexp_match_next(script_ctx_t*,DispatchEx*,DWORD,const WCHAR*,DWORD,const WCHAR**,match_result_t**,
         DWORD*,DWORD*,match_result_t*);
 HRESULT regexp_match(script_ctx_t*,DispatchEx*,const WCHAR*,DWORD,BOOL,match_result_t**,DWORD*);
diff --git a/dlls/jscript/tests/api.js b/dlls/jscript/tests/api.js
index 2fba2520de5..2ccad3dacd7 100644
--- a/dlls/jscript/tests/api.js
+++ b/dlls/jscript/tests/api.js
@@ -2129,7 +2129,7 @@ ok(ActiveXObject.length == 1, "ActiveXObject.length = " + ActiveXObject.length);
 ok(Array.length == 1, "Array.length = " + Array.length);
 ok(Boolean.length == 1, "Boolean.length = " + Boolean.length);
 ok(CollectGarbage.length == 0, "CollectGarbage.length = " + CollectGarbage.length);
-//ok(Date.length == 7, "Date.length = " + Date.length);
+ok(Date.length == 7, "Date.length = " + Date.length);
 ok(Enumerator.length == 7, "Enumerator.length = " + Enumerator.length);
 ok(Error.length == 1, "Error.length = " + Error.length);
 ok(EvalError.length == 1, "EvalError.length = " + EvalError.length);
@@ -2147,7 +2147,7 @@ ok(ScriptEngineMajorVersion.length == 0,
     "ScriptEngineMajorVersion.length = " + ScriptEngineMajorVersion.length);
 ok(ScriptEngineMinorVersion.length == 0,
     "ScriptEngineMinorVersion.length = " + ScriptEngineMinorVersion.length);
-//ok(String.length == 1, "String.length = " + String.length);
+ok(String.length == 1, "String.length = " + String.length);
 ok(SyntaxError.length == 1, "SyntaxError.length = " + SyntaxError.length);
 ok(TypeError.length == 1, "TypeError.length = " + TypeError.length);
 ok(URIError.length == 1, "URIError.length = " + URIError.length);
@@ -2164,4 +2164,7 @@ ok(parseFloat.length == 1, "parseFloat.length = " + parseFloat.length);
 ok(parseInt.length == 2, "parseInt.length = " + parseInt.length);
 ok(unescape.length == 1, "unescape.length = " + unescape.length);
 
+String.length = 3;
+ok(String.length == 1, "String.length = " + String.length);
+
 reportSuccess();