Comment 6 for bug 425334

Sorry for the delay, it took a me a while to get this working. So I downgraded everything but drm-modules-source from xorg-edgers to mesa 7.6.0-1ubuntu2 and then recompiled libgl1-mesa-dri with some troubles to enable r600 support. In the end it turned out well and the fix does seem to be included, desaturated windows work fine.

Except for bug 425303 I didn't find anything else wrong with 7.6. Not-a-benchmark shows >8000 frames/5s, /usr/lib/xscreensaver/gl* all work, wine games work, only blender was easy to crash

drmRadeonCmdBuffer: -22. Kernel failed to parse or rejected command stream.
[ 2975.471078] [drm:radeon_cs_ioctl] *ERROR* cs->dwords too big: 16437

but this looks more like a result of the version mismatch between karmic's libdrm and drm-modules-source from xorg-edgers.