Comment 16 for bug 533784

(In reply to comment #14)
> Are there any NON-gentoo users seeing this bug? :P
>
> (Just to throw in a few more stats, I'm running vanilla kernel sources
> 2.6.33_rc3, and my vcard is: RADEON(0): Chipset: "ATI Mobility Radeon X700
> (M26) (PCIE)" (ChipID = 0x5653) )
>

Here's an example of it on a debian system. There are more mentions on some other mailing lists.
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=563257

This bug report seems to cover this and another problem;
https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/446674