RadFileExplorer allows renaming of extentions with capital letters (e.g. IMG, PNG, etc) even if the FileExplorer's AllowFileExtensionRename="false" property is set. As a result, the renamed extension is appended to the file name, and the original ext is kept.

Video: http://screencast.com/t/MNAZqpRS4o5

Steps to reporduce:
        <telerik:RadFileExplorer ID="RadFileExplorer1" runat="server">
            <Configuration ViewPaths="~/Images" UploadPaths="~/Images" DeletePaths="~/Images" AllowFileExtensionRename="false"/>
        </telerik:RadFileExplorer>

Run the code above and try to rename a file with capital letters extension.