With regard to the RadAjax problem - you are correct that the official Q3 2011 release does not contain a fix for the issue. I hope our dev team will manage to fix it in one of the upcoming releases. You can follow the status of the issue
in our Public Issue Tracking System (PITS).
I have reviewed the sample project and was able to reproduce the "vi-VN" culture issue. It looks like the RadDateInput control does not fully support this culture. The same limitation
exists for Korean culture as well.
Please excuse us for the inconvenience.
the Telerik team
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