Xorg crashed with SIGSEGV in XkbEnableDisableControls()

My X keeps crashing all the time. If I don't do anything, X won't crash, but when I do things like open applications, surf on web etc. X crashes (sooner or later). I haven't found any specific application that would cause it.

Usually X restarts automatically after crash, but sometimes X hangs completely and I have to reboot computer.

I'm using the newest (K)Ubuntu Hardy Heron 8.04 Alpha. The problem exists in all kernels.

Switching back and forth between GDM and KDM (3.5.8 and 4.0) don't have effect.

ProblemType: Crash
Architecture: i386
Date: Mon Feb 25 10:20:09 2008
DistroRelease: Ubuntu 8.04
ExecutablePath: /usr/bin/Xorg
NonfreeKernelModules: cdrom
Package: xserver-xorg-core 2:1.4.1~git20080131-1ubuntu4
PackageArchitecture: i386
ProcCmdline: /usr/bin/X -nolisten tcp :0 vt7 -auth /var/run/xauth/A:0-t3DkHS
ProcCwd: /etc/X11
ProcEnviron: PATH=/bin:/usr/bin:/sbin:/usr/sbin
Signal: 11
SourcePackage: xorg-server
Stacktrace: #0 0x0818f9ea in XkbEnableDisableControls ()
StacktraceTop: XkbEnableDisableControls ()
ThreadStacktrace:

Title: Xorg crashed with SIGSEGV in XkbEnableDisableControls()
Uname: Linux teisei-l 2.6.24-8-generic #1 SMP Thu Feb 14 20:40:45 UTC 2008 i686 GNU/Linux
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