Thanks to all the hard work by the fglrx packaging team, DRI, MESA, Xorg, Radeon,... etc people!
I've been using fglrx with my laptop since I've had it:
01:00.0 VGA compatible controller: ATI Technologies Inc Radeon Mobility X1400
And to the people behind the Debian packaging..
* xserver-xorg-video-radeon from testing.
* libdrm-intel1 and libdrm2 from unstable
* libgl1-mesa-dri and libgl1-mesa-glx from experimental