Thank you for reporting this problem.
I was able to reproduce it and logged it for fixing in our PITS system. We are currently working hard on RadControls for ASP.NET AJAX Q1 2011 and we will be able to investigate this problem after the release, scheduled for the end of next week. Here you can find the PITS Issue and check it status: Public URL
Your Telerik points were updated for your bug report.
the Telerik team
Registration for Q1 2011 What’s New Webinar Week is now open. Mark your calendar for the week starting March 21st and book your seat
for a walk through all the exciting stuff we ship with the new release!