When using a third party skin like replicant or SpinSafe Revolve, the context menu in My TV Home cause a freeze of the whole MP GUI

h4. Steps to Reproduce
Install a skin e.g. relicant or SpinSafe Revolve, go to My TV Home, select Group or Channel, change Channel or Group, GUI freezes

h4. Additional Information
2007-04-16 08:29:13.140625 [ERROR][MPMain]: OnMessage exception:System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
   bei MediaPortal.Dialogs.GUIDialogMenu.OnMessage(GUIMessage message)
   bei MediaPortal.Dialogs.GUIDialogMenu.Close()
   bei MediaPortal.Dialogs.GUIDialogMenu.OnClicked(Int32 controlId, GUIControl control, ActionType actionType)
   bei MediaPortal.GUI.Library.GUIWindow.OnMessage(GUIMessage message)