This code should work with no problem, it is actually used in one of demos
. I have also tested it before writing it here, and can confirm that it works. The server side event also is fired as expected here
If this does not helps, try to insulate the problem in sample runnable web page and send its code to us for further debugging.
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