diff --git a/mozilla/dom/public/base/nsIDOMLocation.h b/mozilla/dom/public/base/nsIDOMLocation.h
index 26e0d74be05..1cf230de15a 100644
--- a/mozilla/dom/public/base/nsIDOMLocation.h
+++ b/mozilla/dom/public/base/nsIDOMLocation.h
@@ -65,6 +65,8 @@ public:
 
   NS_IMETHOD    Replace(const nsAReadableString& aUrl)=0;
 
+  NS_IMETHOD    Assign(const nsAReadableString& aUrl)=0;
+
   NS_IMETHOD    ToString(nsAWritableString& aReturn)=0;
 };
 
@@ -88,6 +90,7 @@ public:
   NS_IMETHOD    SetSearch(const nsAReadableString& aSearch);  \
   NS_IMETHOD    Reload(PRBool aForceget);  \
   NS_IMETHOD    Replace(const nsAReadableString& aUrl);  \
+  NS_IMETHOD    Assign(const nsAReadableString& aUrl);  \
   NS_IMETHOD    ToString(nsAWritableString& aReturn);  \
 
 
@@ -111,6 +114,7 @@ public:
   NS_IMETHOD    SetSearch(const nsAReadableString& aSearch) { return _to SetSearch(aSearch); } \
   NS_IMETHOD    Reload(PRBool aForceget) { return _to Reload(aForceget); }  \
   NS_IMETHOD    Replace(const nsAReadableString& aUrl) { return _to Replace(aUrl); }  \
+  NS_IMETHOD    Assign(const nsAReadableString& aUrl) { return _to Assign(aUrl); }  \
   NS_IMETHOD    ToString(nsAWritableString& aReturn) { return _to ToString(aReturn); }  \
 
 
diff --git a/mozilla/dom/public/idl/base/Location.idl b/mozilla/dom/public/idl/base/Location.idl
index c076a00dd1e..8f53af251ca 100644
--- a/mozilla/dom/public/idl/base/Location.idl
+++ b/mozilla/dom/public/idl/base/Location.idl
@@ -1,25 +1,26 @@
-      interface Location {
+interface Location {
 /* IID: { 0xa6cf906d, 0x15b3, 0x11d2, \
   { 0x93, 0x2e, 0x00, 0x80, 0x5f, 0x8a, 0xdd, 0x32 } } */
 
-	attribute wstring hash;
+        attribute wstring hash;
         attribute wstring host;
-	attribute wstring hostname;
+        attribute wstring hostname;
         noscript attribute wstring href;
         attribute wstring pathname;
         attribute wstring port;
         attribute wstring protocol;
         attribute wstring search;
 
-	noscript void reload(in boolean forceget);
+        noscript void reload(in boolean forceget);
         noscript void replace(in wstring url);
+        void assign(in wstring url);
 
-	wstring toString();
-      };
+        wstring toString();
+};
 
-      interface NSLocation {
+interface NSLocation {
 /* IID: { 0xa6cf9108, 0x15b3, 0x11d2, \
   { 0x93, 0x2e, 0x00, 0x80, 0x5f, 0x8a, 0xdd, 0x32 } } */
         void reload(/* ... */);
         void replace(/* ... */);
-      };
+};
diff --git a/mozilla/dom/public/nsDOMPropEnums.h b/mozilla/dom/public/nsDOMPropEnums.h
index fd259c72361..959eb962ee3 100644
--- a/mozilla/dom/public/nsDOMPropEnums.h
+++ b/mozilla/dom/public/nsDOMPropEnums.h
@@ -677,6 +677,7 @@ enum nsDOMProp {
     NS_DOM_PROP_KEYEVENT_METAKEY, 
     NS_DOM_PROP_KEYEVENT_SHIFTKEY, 
     NS_DOM_PROP_LINKSTYLE_SHEET,
+    NS_DOM_PROP_LOCATION_ASSIGN, 
     NS_DOM_PROP_LOCATION_HASH, 
     NS_DOM_PROP_LOCATION_HOST, 
     NS_DOM_PROP_LOCATION_HOSTNAME, 
diff --git a/mozilla/dom/public/nsDOMPropNames.h b/mozilla/dom/public/nsDOMPropNames.h
index 423cd40cfd6..89f107d1f8e 100644
--- a/mozilla/dom/public/nsDOMPropNames.h
+++ b/mozilla/dom/public/nsDOMPropNames.h
@@ -675,6 +675,7 @@
     "keyevent.metakey", \
     "keyevent.shiftkey", \
     "linkstyle.sheet", \
+    "location.assign", \
     "location.hash", \
     "location.host", \
     "location.hostname", \
diff --git a/mozilla/dom/src/base/nsGlobalWindow.h b/mozilla/dom/src/base/nsGlobalWindow.h
index 52d44e491ce..677a9d76282 100644
--- a/mozilla/dom/src/base/nsGlobalWindow.h
+++ b/mozilla/dom/src/base/nsGlobalWindow.h
@@ -348,6 +348,7 @@ public:
    NS_IMETHOD    SetSearch(const nsAReadableString& aSearch);
    NS_IMETHOD    Reload(PRBool aForceget);
    NS_IMETHOD    Replace(const nsAReadableString& aUrl);
+   NS_IMETHOD    Assign(const nsAReadableString& aUrl);
    NS_IMETHOD    ToString(nsAWritableString& aReturn);
 
    // nsIDOMNSLocation
diff --git a/mozilla/dom/src/base/nsJSLocation.cpp b/mozilla/dom/src/base/nsJSLocation.cpp
index e1482cd9d66..b9f4a12e707 100644
--- a/mozilla/dom/src/base/nsJSLocation.cpp
+++ b/mozilla/dom/src/base/nsJSLocation.cpp
@@ -322,6 +322,47 @@ ResolveLocation(JSContext *cx, JSObject *obj, jsval id)
 }
 
 
+//
+// Native method Assign
+//
+PR_STATIC_CALLBACK(JSBool)
+LocationAssign(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
+{
+  nsIDOMLocation *nativeThis = (nsIDOMLocation*)nsJSUtils::nsGetNativeThis(cx, obj);
+  nsresult result = NS_OK;
+  nsAutoString b0;
+  // If there's no private data, this must be the prototype, so ignore
+  if (nsnull == nativeThis) {
+    return JS_TRUE;
+  }
+
+  {
+    *rval = JSVAL_NULL;
+    nsIScriptSecurityManager *secMan = nsJSUtils::nsGetSecurityManager(cx, obj);
+    if (!secMan)
+        return PR_FALSE;
+    result = secMan->CheckScriptAccess(cx, obj, NS_DOM_PROP_LOCATION_ASSIGN, PR_FALSE);
+    if (NS_FAILED(result)) {
+      return nsJSUtils::nsReportError(cx, obj, result);
+    }
+    if (argc < 1) {
+      return nsJSUtils::nsReportError(cx, obj, NS_ERROR_DOM_TOO_FEW_PARAMETERS_ERR);
+    }
+
+    nsJSUtils::nsConvertJSValToString(b0, cx, argv[0]);
+
+    result = nativeThis->Assign(b0);
+    if (NS_FAILED(result)) {
+      return nsJSUtils::nsReportError(cx, obj, result);
+    }
+
+    *rval = JSVAL_VOID;
+  }
+
+  return JS_TRUE;
+}
+
+
 //
 // Native method ToString
 //
@@ -479,6 +520,7 @@ static JSPropertySpec LocationProperties[] =
 //
 static JSFunctionSpec LocationMethods[] = 
 {
+  {"assign",          LocationAssign,     1},
   {"toString",          LocationToString,     0},
   {"reload",          NSLocationReload,     0},
   {"replace",          NSLocationReplace,     0},
diff --git a/mozilla/dom/src/base/nsLocation.cpp b/mozilla/dom/src/base/nsLocation.cpp
index f86b7af3ae7..3d3d6d8ab86 100644
--- a/mozilla/dom/src/base/nsLocation.cpp
+++ b/mozilla/dom/src/base/nsLocation.cpp
@@ -639,6 +639,24 @@ LocationImpl::Replace(const nsAReadableString& aUrl)
   return result;
 }
 
+NS_IMETHODIMP    
+LocationImpl::Assign(const nsAReadableString& aUrl)
+{
+  nsAutoString oldHref;
+  nsCOMPtr<nsIURI> oldUrl;
+  nsresult result = NS_OK;
+
+  result = GetHref(oldHref);
+  if (NS_SUCCEEDED(result)) {
+    result = NS_NewURI(getter_AddRefs(oldUrl), oldHref);
+    if (NS_SUCCEEDED(result)) {
+      result = SetHrefWithBase(aUrl, oldUrl, PR_FALSE);
+    }
+  }
+
+  return result;
+}
+
 NS_IMETHODIMP    
 LocationImpl::Reload(JSContext *cx, jsval *argv, PRUint32 argc)
 {