Xorg crashed with SIGABRT in raise()

Ubuntu suddenly informed me about a crash and reported this one.

ProblemType: Crash
DistroRelease: Ubuntu 12.10
Package: xserver-xorg-core 2:1.13.0-0ubuntu5
ProcVersionSignature: Ubuntu 3.5.0-16.25-generic 3.5.4
Uname: Linux 3.5.0-16-generic x86_64
NonfreeKernelModules: wl
.tmp.unity.support.test.0:

ApportVersion: 2.5.3-0ubuntu1
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CrashCounter: 1
Date: Sun Sep 30 11:40:12 2012
DistUpgraded: Fresh install
DistroCodename: quantal
DistroVariant: ubuntu
DkmsStatus:
 bcmwl, 5.100.82.112+bdcom, 3.5.0-15-generic, x86_64: installed
 bcmwl, 5.100.82.112+bdcom, 3.5.0-16-generic, x86_64: installed
ExecutablePath: /usr/bin/Xorg
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Samsung Electronics Co Ltd Device [144d:c0b3]
 Advanced Micro Devices [AMD] nee ATI Caicos [Radeon HD 6400M/7400M Series] [1002:6760] (prog-if 00 [VGA controller])
   Subsystem: Samsung Electronics Co Ltd Device [144d:c0b3]
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Beta amd64 (20120926)
MachineType: SAMSUNG ELECTRONICS CO., LTD. 700Z3A/700Z4A/700Z5A/700Z5B
ProcCmdline: /usr/bin/X :0 -core -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
ProcEnviron:

ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-16-generic root=UUID=74b48ab1-0d2b-4023-bc87-c3e30a4aea3f ro quiet splash vt.handoff=7
Signal: 6
SourcePackage: xorg-server
StacktraceTop:
 raise () from /lib/x86_64-linux-gnu/libc.so.6
 abort () from /lib/x86_64-linux-gnu/libc.so.6
 OsAbort ()
 ?? ()
 FatalError ()
Title: Xorg crashed with SIGABRT in raise()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

dmi.bios.date: 03/29/2012
dmi.bios.vendor: Phoenix Technologies Ltd.
dmi.bios.version: 13FD
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: 700Z3A/700Z4A/700Z5A/700Z5B
dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD.
dmi.board.version: FAB1
dmi.chassis.asset.tag: Asset Tag
dmi.chassis.type: 9
dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD.
dmi.chassis.version: 0.1
dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvr13FD:bd03/29/2012:svnSAMSUNGELECTRONICSCO.,LTD.:pn700Z3A/700Z4A/700Z5A/700Z5B:pvr0.1:rvnSAMSUNGELECTRONICSCO.,LTD.:rn700Z3A/700Z4A/700Z5A/700Z5B:rvrFAB1:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvr0.1:
dmi.product.name: 700Z3A/700Z4A/700Z5A/700Z5B
dmi.product.version: 0.1
dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD.
version.compiz: compiz 1:0.9.8.2+bzr3377-0ubuntu1
version.ia32-libs: ia32-libs 20090808ubuntu36
version.libdrm2: libdrm2 2.4.39-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.0~git20120917.7cfd42ce-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.0~git20120917.7cfd42ce-0ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.13.0-0ubuntu5
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.99.99~git20120913.8637f772-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.20.9-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.2-0ubuntu2