If you're using the xorg-driver-fglrx from the Ubuntu repositories, I'm assuming that there's an older version contained somewhere on it, though I havn't the foggiest idea where or how. You can probably look it up easily enough though from the Ubuntu forums.

Or if you installed fglrx using the ATI installer, just grab an older version from the ATI website and run it and see if it works, YMMV.