First the blog says:
> The good news is that this bug has been fixed in Visual Studio 2008 SP1!
I've already installed SP1 (see my post above)
> Copy Telerik.Web.Design.dll to your web site ...
sorry, but there is no file "Telerik.Web.Design.dll" im my [RadControlASPNET AJAX Q2 2008] package
> Copy Telerik.Web.UI.dll to c:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE\PublicAssemblies
that did not help :)