Comment # 29 on bug 102358 from haro41@gmx.de

I tried both: mesa_glthread=false/true, it doesn't make a difference in respect
to this issue.

It think other applications/games could be affected by this problem too, so
maybe temporary reverting the changes in dri2_flush_swapbuffers() would make
sense? 

(this is currently my approach to avoid the freezes)