Comment 2 for bug 1233540

[ 189.548] (EE) Backtrace:
[ 189.549] (EE) 0: /usr/bin/X (xorg_backtrace+0x49) [0xb76db1f9]
[ 189.549] (EE) 1: /usr/bin/X (0xb753b000+0x1a3f64) [0xb76def64]
[ 189.549] (EE) 2: (vdso) (__kernel_rt_sigreturn+0x0) [0xb751840c]
[ 189.549] (EE) 3: /usr/lib/xorg/modules/extensions/libglx.so (0xb6c5f000+0x46c6e) [0xb6ca5c6e]
[ 189.549] (EE) 4: /usr/lib/xorg/modules/extensions/libglx.so (0xb6c5f000+0x46e3f) [0xb6ca5e3f]
[ 189.549] (EE) 5: /usr/lib/xorg/modules/extensions/libglx.so (0xb6c5f000+0x429be) [0xb6ca19be]
[ 189.550] (EE) 6: /usr/bin/X (0xb753b000+0x3c48d) [0xb757748d]
[ 189.550] (EE) 7: /usr/bin/X (0xb753b000+0x2a52a) [0xb756552a]
[ 189.550] (EE) 8: /lib/i386-linux-gnu/libc.so.6 (__libc_start_main+0xf5) [0xb7114905]
[ 189.550] (EE) 9: /usr/bin/X (0xb753b000+0x2a908) [0xb7565908]
[ 189.550] (EE)
[ 189.550] (EE) Segmentation fault at address 0x44c
[ 189.550] (EE)
Fatal server error:
[ 189.550] (EE) Caught signal 11 (Segmentation fault). Server aborting