The described issue is very strange. We have not encountered it so far and we are not sure what could be the reason for experiencing the problem. Could you please try isolating the problem in a simple example and send it to us. You could open a formal support ticket from your Telerik account and attach a ZIP file there. Thus we will be able to gather more details about your scenario debug the application and investigate the problem.
Looking forward for your reply.
the Telerik team
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed