I'm running Ubuntu Gutsy (up to date) with Catalyst 8.01 ATI driver on a Macbook Pro. I'm quite the linux enthusiast, but I have never (not with any fglrx version the last two years) gotten dual screen / secondary display working.

Now I'm tired of waiting for a fix so I was hoping you guys could help me out!

The laptop's default resolution is 1680x1050. The secondary display's (maximum) resolution is 1280x1024.

I got it working with the vesa driver, but that wasn't satisfying. I've done all sorts of changes in the ATI Catalyst Control Center both as user and as root with "sudo amdcccle".
It does find my secondary display.
It does change my resolution,
but it does not clone or expand the display over to the other screen (even though I've checked the corresponding box).

As I boot my machine the grub text appears on both screens.
The Ubuntu loading splash appears on both screens,
but as gnome / gdm starts, the secondary display dies out. I've tried this with several screens and projectors. I've even tried it with another macbook. I've never gotten it working. So I find it kind of weird that I'm not able to get an answer from google.
Anyways..

Does it work for you?
How can I get the secondary screen working?