Did you test the project Svetlina sent you - what was the result? In case you cannot reproduce the problem with that project, probably the cause for the multiple scrollbars you describe is in the page you load in the RadPane, not in the RadPane itself. The easiest way to test whether you have configured the TooLongContent page correctly, is to open it is a simple IFRAME element as Svetlina suggested.
In case you need additional help, please prepare and send us a simple running project, demonstrating the problem so that we are able to investigate what is causing it on our side.
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