Not real sure what you mean by taking over their BlackBerry. Nothing can take over their BlackBerry. What functionality have they lost in particular. I know that a WebSense server can cause browsing issues because it adds info into the header causing it to be too large I think.
Here is RIM's article on that: http://www.blackberry.com/btsc/searc...200%2042850147
Review that as some changes need to be made on the Websense server if that's the case.
If you are experiencing something else then please explain.