compiz crashed with SIGSEGV in sigc::signal_base::impl()

[Azet]

Binary package hint: unity

?

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: unity 3.8.4-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.38-8.41-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic i686
NonfreeKernelModules: nvidia
Architecture: i386
CrashCounter: 1
Date: Sun Apr 17 23:07:40 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=en_US:en
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x53ce3d <_ZNK4sigc11signal_base4implEv+29>: mov 0x4(%edi),%esi
 PC (0x0053ce3d) ok
 source "0x4(%edi)" (0x0000007c) not located in a known VMA region (needed readable region)!
 destination "%esi" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 sigc::signal_base::impl() const () from /usr/lib/libsigc-2.0.so.0
 sigc::signal_base::connect(sigc::slot_base const&) () from /usr/lib/libsigc-2.0.so.0
 UnityScreen::UnityScreen(CompScreen*) () from /usr/lib/compiz/libunityshell.so
 CompPlugin::VTableForScreenAndWindow<UnityScreen, UnityWindow>::initScreen(CompScreen*) () from /usr/lib/compiz/libunityshell.so
 CompManager::initPlugin(CompPlugin*) ()
Title: compiz crashed with SIGSEGV in sigc::signal_base::impl()
UpgradeStatus: Upgraded to natty on 2011-04-15 (2 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

[Apport retracing service (apport)]

StacktraceTop:
 sigc::signal_base::impl (this=0x78) at ../../sigc++/signal_base.cc:145
 sigc::signal_base::connect (this=0x78, slot_=...) at ../../sigc++/signal_base.cc:122
 get_vtable (this=0x8a68ed8, screen=0x85074b8) at /usr/include/boost/function/function_template.hpp:680
 move_assign (this=0x8a68ed8, screen=0x85074b8) at /usr/include/boost/function/function_template.hpp:974
 swap (this=0x8a68ed8, screen=0x85074b8) at /usr/include/boost/function/function_template.hpp:846