compiz crashed with SIGSEGV in nux::WindowCompositor::RenderTopViews()

[LiohMoeller]

compiz suddenly crashed

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: libnux-0.9-0 0.9.38-0ubuntu1
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: Sun Apr 3 08:45:28 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110330)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=de:en
 LANG=de_CH.UTF-8
 LC_MESSAGES=de_DE.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0xb4a59abb <_ZN3nux16WindowCompositor14RenderTopViewsEbRSt4listINS_13ObjectWeakPtrINS_10BaseWindowEEESaIS4_EEbb+2171>: mov 0x10(%edx),%eax
 PC (0xb4a59abb) ok
 source "0x10(%edx)" (0x00000031) not located in a known VMA region (needed readable region)!
 destination "%eax" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: nux
StacktraceTop:
 nux::WindowCompositor::RenderTopViews(bool, std::list<nux::ObjectWeakPtr<nux::BaseWindow>, std::allocator<nux::ObjectWeakPtr<nux::BaseWindow> > >&, bool, bool) () from /usr/lib/libnux-0.9.so.0
 nux::WindowCompositor::Draw(bool, bool) () from /usr/lib/libnux-0.9.so.0
 nux::WindowThread::RenderInterfaceFromForeignCmd(nux::Rect*) () from /usr/lib/libnux-0.9.so.0
 UnityScreen::paintDisplay(CompRegion const&) () from /usr/lib/compiz/libunityshell.so
 UnityWindow::glDraw(GLMatrix const&, GLFragment::Attrib&, CompRegion const&, unsigned int) () from /usr/lib/compiz/libunityshell.so
Title: compiz crashed with SIGSEGV in nux::WindowCompositor::RenderTopViews()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare