System Environment:
--------------------------

--Platform:Q35

--Architecture(32-bit,64-bit,compatiblity):64bit 

--2D driver:
commit f69b48fe24ef94dac44b8123884ca71df675be4b

--3D driver:
commit 8aa0fd6b206930ababb1bae2acc629e2a945c0c0

--Xserver:
commit 7ef7727b800fa4715b80a82850d65b88fde5fe6c


--Kernel:
2.6.24-rc5


Bug detailed description:
-------------------------
startx ,run quake4  ,and the game abort and crash x.
and we update the mesa to latest version , problem still exist.



Reproduce steps:
----------------
 run quake4-demo



Current result:
----------------
abort,and crash X 


Expected result:
----------------
run normally