diff --git a/dlls/inetcomm/mimeole.c b/dlls/inetcomm/mimeole.c
index 38dd46b4444..6b5c75d16c5 100644
--- a/dlls/inetcomm/mimeole.c
+++ b/dlls/inetcomm/mimeole.c
@@ -268,6 +268,39 @@ static void unfold_header(char *header, int len)
     *(start - 1) = '\0';
 }
 
+static char *unquote_string(const char *str)
+{
+    int quoted = 0;
+    char *ret, *cp;
+
+    while(*str == ' ' || *str == '\t') str++;
+
+    if(*str == '"')
+    {
+        quoted = 1;
+        str++;
+    }
+    ret = strdupA(str);
+    for(cp = ret; *cp; cp++)
+    {
+        if(*cp == '\\')
+            memmove(cp, cp + 1, strlen(cp + 1) + 1);
+        else if(*cp == '"')
+        {
+            if(!quoted)
+            {
+                WARN("quote in unquoted string\n");
+            }
+            else
+            {
+                *cp = '\0';
+                break;
+            }
+        }
+    }
+    return ret;
+}
+
 static void add_param(header_t *header, const char *p)
 {
     const char *key = p, *value, *cp = p;
@@ -293,7 +326,7 @@ static void add_param(header_t *header, const char *p)
 
     param = HeapAlloc(GetProcessHeap(), 0, sizeof(*param));
     param->name = name;
-    param->value = strdupA(value);
+    param->value = unquote_string(value);
     list_add_tail(&header->params, &param->entry);
 }
 
diff --git a/dlls/inetcomm/tests/mimeole.c b/dlls/inetcomm/tests/mimeole.c
index c36502e2bee..f5cd619da92 100644
--- a/dlls/inetcomm/tests/mimeole.c
+++ b/dlls/inetcomm/tests/mimeole.c
@@ -36,7 +36,8 @@ static char msg1[] =
     "MIME-Version: 1.0\r\n"
     "Content-Type: multipart/mixed;\r\n"
     " boundary=\"------------1.5.0.6\";\r\n"
-    " stuff=\"du;nno\"\r\n"
+    " stuff=\"du;nno\";\r\n"
+    " morestuff=\"so\\\\me\\\"thing\\\"\"\r\n"
     "foo: bar\r\n"
     "From: Huw Davies <huw@codeweavers.com>\r\n"
     "From: Me <xxx@codeweavers.com>\r\n"
@@ -90,7 +91,7 @@ static void test_CreateBody(void)
     LARGE_INTEGER off;
     ULARGE_INTEGER pos;
     ENCODINGTYPE enc;
-    ULONG count;
+    ULONG count, found_param, i;
     MIMEPARAMINFO *param_info;
     IMimeAllocator *alloc;
 
@@ -119,7 +120,7 @@ static void test_CreateBody(void)
     ok(hr == S_OK, "ret %08x\n", hr);
     off.QuadPart = 0;
     IStream_Seek(in, off, STREAM_SEEK_CUR, &pos);
-    ok(pos.u.LowPart == 328, "pos %u\n", pos.u.LowPart);
+    ok(pos.u.LowPart == 359, "pos %u\n", pos.u.LowPart);
 
     hr = IMimeBody_IsContentType(body, "multipart", "mixed");
     ok(hr == S_OK, "ret %08x\n", hr);
@@ -153,9 +154,27 @@ static void test_CreateBody(void)
     hr = IMimeBody_GetParameters(body, "Content-Type", &count, &param_info);
     ok(hr == S_OK, "ret %08x\n", hr);
     todo_wine  /* native adds a charset parameter */
-        ok(count == 3, "got %d\n", count);
+        ok(count == 4, "got %d\n", count);
     ok(param_info != NULL, "got %p\n", param_info);
 
+    found_param = 0;
+    for(i = 0; i < count; i++)
+    {
+        if(!strcmp(param_info[i].pszName, "morestuff"))
+        {
+            found_param++;
+            ok(!strcmp(param_info[i].pszData, "so\\me\"thing\""),
+               "got %s\n", param_info[i].pszData);
+        }
+        else if(!strcmp(param_info[i].pszName, "stuff"))
+        {
+            found_param++;
+            ok(!strcmp(param_info[i].pszData, "du;nno"),
+               "got %s\n", param_info[i].pszData);
+        }
+    }
+    ok(found_param == 2, "matched %d params\n", found_param);
+
     hr = IMimeAllocator_FreeParamInfoArray(alloc, count, param_info, TRUE);
     ok(hr == S_OK, "ret %08x\n", hr);
     IMimeAllocator_Release(alloc);