Me (stupid me), upgraded Debian, and I got the same problem. Now I have both Gentoo and Debian with buggy Xorgs.

How did I solve it? Whenever I boot Linux, I don't use X anymore ... .==;
I just use that text-based X thing (forgot the name) or MOL. And for watching videos and stuff I boot MorphOS...

I don't have Internet at home anymore, so I stopped "playing to be a debugger" ...

Hi!
I know, not very funny installing it without internet, but xorg 7.1 seems to have all patches from Benjamin Herrenschmidt (mentioned by morgoth before) already
included - i.e. it works "out of the box"...

I brought the computer to a place with inet connection ;)

And I emerged xorg-x11 7.1, but it didn't compile any radeon or ati drivers! I have VIDEO_CARDS="radeon" in my /etc/make.conf

Has this changed in the new xorg?
How do I bring the drivers?

Did you emerge xf86-video-ati?
Usually it should be included with your emerge xorg-x11 (?),
but maybe it was somehow forgotten...

It seems that when I emerged the 7.1, it didn't update the packages under x11-drivers (keyboard, video-ati, etc)... So I emerged only those separately and now it works. (I had xf86-video-ati 1.0 and now 1.1 ) :D

It seems I don't get any more crashes :) But the DRI isn't working :(

update mesa and make sure your kernel module is ok