I'm currently using an ATI binary driver for X 4.3. I got it here:

http://www.schneider-digital.de/html/body_download_ati.html

I'm using the FireGL X1/Z1 driver. If anybody wants to try the FireGL 8x00 driver, let us know how it works for you.

Ummm... Why do you have a FireGL?

Oh, I guess I didn't mention that I have a Radeon 9000 Pro (128 MB DDR).
It's not a FireGL, but the drivers on that site work fine.
The description says "Linux Fire GL X1 / RADEON Driver"

ATI's doing the unified driver like nVidia. Apparently it's easier to maintain that way.