Hello Idsert Jongema,
Yes, you need to download the latest version of Telerik.Web.UI (v. 2008.2.723) from your Client.NET account.
Along with the localization changes, another benefit is that RadUpload now works properly in IIS 7
You can check the What's New
section and Changes and backward compatibility page.
I hope this helps.
the Telerik team
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