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

[steveacab]

Binary package hint: unity

crash on check "window blur" in ccsm

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: unity 3.6.8-0ubuntu3 [modified: usr/lib/unity/unity-panel-service]
ProcVersionSignature: Ubuntu 2.6.38-7.39-generic-pae 2.6.38
Uname: Linux 2.6.38-7-generic-pae i686
Architecture: i386
CrashCounter: 1
Date: Fri Apr 1 15:21:56 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110302)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=it_IT:en
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x4257be3d <_ZNK4sigc11signal_base4implEv+29>: mov 0x4(%edi),%esi
 PC (0x4257be3d) 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 2011-03-26 (6 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
 ?? () from /usr/lib/compiz/libunityshell.so
 ?? () from /usr/lib/compiz/libunityshell.so
 CompManager::initPlugin (p=0xa2faad0) at /build/buildd/compiz-0.9.4git20110322/src/plugin.cpp:280