compiz crashed with SIGSEGV in PrivateWindow::configureFrame()

[manatorg]

tried to change workspace an then the crash happend

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: unity 4.20.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-12.19-generic 3.0.4
Uname: Linux 3.0.0-12-generic i686
ApportVersion: 1.23-0ubuntu2
Architecture: i386
CrashCounter: 1
Date: Mon Oct 3 09:45:13 2011
ExecutablePath: /usr/bin/compiz
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=de_DE:en
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x8088cc0 <_ZN13PrivateWindow14configureFrameEP15XConfigureEvent+144>: mov 0x34(%eax),%edx
 PC (0x08088cc0) ok
 source "0x34(%eax)" (0x00000034) not located in a known VMA region (needed readable region)!
 destination "%edx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 PrivateWindow::configureFrame(XConfigureEvent*) ()
 CompScreen::handleEvent(_XEvent*) ()
 PrivateCompositeScreen::handleEvent(_XEvent*) () from /usr/lib/compiz/libcomposite.so
 CompScreen::handleEvent(_XEvent*) ()
 PrivateGLScreen::handleEvent(_XEvent*) () from /usr/lib/compiz/libopengl.so
Title: compiz crashed with SIGSEGV in PrivateWindow::configureFrame()
UpgradeStatus: Upgraded to oneiric on 2011-10-01 (1 days ago)
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