I just tried that but cannot get the error:
I change the data the first time, but does not submit the change, should I? Moving forth and back to the same page and changing/updating the same value functions properly and the value is updated without any error.
The demo runs with the new version of RadControls for ASP.NET AJAX Q2 2008 Service Pack 1
but we have not changed the demo recently. Let us know if I'm missing a detail from the required steps.
All the best,
the Telerik team
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