yep, I also pushed a fix for G33 in xf86-video-intel when fixing the intel agp.
So for G33 user, you should upgrade both to be able to work correctly.
It looks you have an old version of mesa, that i915 dri driver doesn't know
your chipset. Try mesa-7.X.
I have also seen X exit broken with 2.6.23-rc6-mm1, will follow this thread
and try Dave's patch.
Thanks for testing!
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