Could you please test the application by disable the Ajax on the page and let me know if this makes any difference. Also please try using regular asp UpdatePanel instead of RadAjax and verify what the result is.
All the best,
the Telerik team
Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items