kwin crashed at startup

[NiWie]

kwin gives a message shortly aufter boot. but i dont know why. it is no problem visible.
Using Kubuntu 9.10, upgradet from 9.04.

ProblemType: Crash
Architecture: i386
CrashCounter: 1
Date: Tue Nov 3 00:18:06 2009
DistroRelease: Ubuntu 9.10
ExecutablePath: /usr/share/apport/apport-kde
InterpreterPath: /usr/bin/python2.6
NonfreeKernelModules: nvidia
Package: apport-kde 1.9.3-0ubuntu4
PackageArchitecture: all
ProcCmdline: /usr/bin/python /usr/share/apport/apport-kde
ProcEnviron:
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
 LANGUAGE=
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
SegvAnalysis:
 Segfault happened at: 0x75adf32: mov 0x8(%eax),%eax
 PC (0x075adf32) ok
 source "0x8(%eax)" (0x00000008) not located in a known VMA region (needed readable region)!
 destination "%eax" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: apport
StacktraceTop:
 ?? () from /usr/lib/libQtGui.so.4
 ?? () from /usr/lib/libQtGui.so.4
 QWidgetPrivate::deleteExtra() () from /usr/lib/libQtGui.so.4
 QWidgetPrivate::~QWidgetPrivate() ()
 ?? () from /usr/lib/libQtGui.so.4
Title: apport-kde crashed with SIGSEGV in QWidgetPrivate::deleteExtra()
Uname: Linux 2.6.31-14-generic i686
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
XsessionErrors: (polkit-gnome-authentication-agent-1:5970): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make Ubuntu better. This particular crash has already been reported and is a duplicate of bug #403361, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.