compiz crashed with SIGSEGV in unity::switcher::SwitcherController::~SwitcherController()

Appeared shortly after session start, no visible cause

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: unity 4.20.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-12.19-generic-pae 3.0.4
Uname: Linux 3.0.0-12-generic-pae i686
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu2
Architecture: i386
CrashCounter: 1
Date: Sun Oct 2 08:44:27 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
ProcCmdline: compiz
ProcEnviron:
 PATH=(cususername, user)
 LANG=cs_CZ.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0xb36e61a3 <_ZN5unity8switcher18SwitcherControllerD2Ev+35>: mov (%eax),%edx
 PC (0xb36e61a3) ok
 source "(%eax)" (0x00000000) not located in a known VMA region (needed readable region)!
 destination "%edx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 unity::switcher::SwitcherController::~SwitcherController() () from /usr/lib/compiz/libunityshell.so
 unity::switcher::SwitcherController::~SwitcherController() () from /usr/lib/compiz/libunityshell.so
 UnityScreen::~UnityScreen() () from /usr/lib/compiz/libunityshell.so
 UnityScreen::~UnityScreen() () from /usr/lib/compiz/libunityshell.so
 CompPlugin::VTableForScreenAndWindow<UnityScreen, UnityWindow>::finiScreen(CompScreen*) () from /usr/lib/compiz/libunityshell.so
Title: compiz crashed with SIGSEGV in unity::switcher::SwitcherController::~SwitcherController()
UpgradeStatus: Upgraded to oneiric on 2011-09-28 (3 days ago)
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