compiz crashed with SIGSEGV in operator--()

Binary package hint: unity

 Description: Ubuntu Natty (development branch)
Release: 11.04

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
Architecture: i386
Date: Fri Apr 8 00:06:37 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110318)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=it_IT:en
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x3928728 <nux::WindowCompositor::RenderTopViews(bool, std::list<nux::ObjectWeakPtr<nux::BaseWindow>, std::allocator<nux::ObjectWeakPtr<nux::BaseWindow> > >&, bool, bool)+88>: mov 0x4(%esi),%edx
 PC (0x03928728) ok
 source "0x4(%esi)" (0x43c20004) not located in a known VMA region (needed readable region)!
 destination "%edx" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: unity
StacktraceTop:
 operator-- (this=0xa2d1468, force_draw=false, WindowList=..., drawModal=false, use_fbo=true) at /usr/include/c++/4.5/bits/stl_list.h:158
 operator* (this=0xa2d1468, force_draw=false, WindowList=..., drawModal=false, use_fbo=true) at /usr/include/c++/4.5/bits/stl_iterator.h:157
 nux::WindowCompositor::RenderTopViews (this=0xa2d1468, force_draw=false, WindowList=..., drawModal=false, use_fbo=true) at ./WindowCompositor.cpp:1059
 nux::WindowCompositor::Draw (this=0xa2d1468, SizeConfigurationEvent=false, force_draw=false) at ./WindowCompositor.cpp:884
 nux::WindowThread::RenderInterfaceFromForeignCmd (this=0xa1c4e78, clip=0xbfc2a930) at ./WindowThread.cpp:1850
Title: compiz crashed with SIGSEGV in operator--()
UpgradeStatus: No upgrade log present (probably fresh install)
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