Reflection and late binding in Silverlight

Question

I want to be able to load items in System.Windows.Controls using late binding.

I can do it with dlls that i can load remotely like this:

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        panel1.Children.Clear();

        WebClient c = new WebClient();
        c.OpenReadCompleted += new OpenReadCompletedEventHandler(c_OpenReadCompleted);
        c.OpenReadAsync(new Uri("DynamicXapDataGrid_CS.xap", UriKind.Relative));
    }

    void c_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
    {
        string appManifest = new StreamReader(Application.GetResourceStream(new StreamResourceInfo(e.Result, null), new Uri("AppManifest.xaml", UriKind.Relative)).Stream).ReadToEnd();

        XElement deploy = XDocument.Parse(appManifest).Root;
        List<XElement> parts = (from assemblyParts in deploy.Elements().Elements()
                                select assemblyParts).ToList();

        Assembly asm = null;

        foreach (XElement xe in parts)
        {
            string source = xe.Attribute("Source").Value;

            AssemblyPart asmPart = new AssemblyPart();

            StreamResourceInfo streamInfo = Application.GetResourceStream(new StreamResourceInfo(e.Result, "application/binary"), new Uri(source, UriKind.Relative));

            if (source == "DynamicXapDataGrid_CS.dll")
            {
                asm = asmPart.Load(streamInfo.Stream);
            }
            else
            {
                asmPart.Load(streamInfo.Stream);
            }
        }

        panel1.DataContext = FakeData.GetCustomers(LastNameSearch.Text);

        UIElement myData = asm.CreateInstance("DynamicXapDataGrid_CS.Page") as UIElement;

        panel1.Children.Add(myData);
        panel1.UpdateLayout();

    }

the problem comes when i want to load, say a Grid.

 Assembly asm = Assembly.GetCallingAssembly();

  UIElement element = null;

  try { element = asm.CreateInstance("System.Windows.Controls.Grid") as UIElement; } catch { }

is always null. I assume that i may need the fully qualified name for Grid, but i have been Googling this for hours now with no solution. Any help would be appreciated.