This is the expected behavior of pages loaded in iframes - they modify only their own context.
Perhaps what you need is a frame buster that will let your pages go to the top frame if you need them to. You can see simple examples here: http://www.telerik.com/help/aspnet-ajax/window-application-is-page-in-radwindow.html
and look in the net for more options (like automatically clicking anchors with target=_top).
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