Thank you for reporting this issue. We have verified that it is a bug in the external CSS resources (the link should be http://aspnet-skins.telerikstatic.com/ajaxz/2010.3.1215/Default/FormDecorator/ButtonSprites.gif (Default instead of Forest). We will fix this for the next service pack release of the RadControls suite.
Kind regards,
Lini
the Telerik team
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