Comment 10 for bug 564617

Here are the different versions of libraries used by ubuntu (I don't know which ones are relevant in this case) :

On beta 2 (with all current updates) :
xorg 1:7.5+5ubuntu1
libdrmnouveau1 2.4.18-1ubuntu3
xserver-xorg-video-nouveau 1:0.0.15+git20100219+9b4118d-0ubuntu5
kernel 2.6.32-21-generic (on x86)

On alpha 3 liveCD :
xorg 1:7.5+1ubuntu8
libdrmnouveau1 2.4.18-1ubuntu2
xserver-xorg-video-nouveau 1:0.0.15+git20100219+9b4118d-0ubuntu2
kernel 2.6.32-14-generic (on x86)