Can't imagine a good reason to do that, but ... I'd try apt-get remove --purge xorg ... then change your sources list to stable, and do apt-get install x-windows-system.
I think you're going to run into major problems. Would probably be better to reinstall Sarge from scratch leaving /home intact. Of course that assumes that you have /home on a separate partition. Everybody should.
Last edited by rickh; 07-05-2006 at 11:19 PM.