nepomukservicestub crashed with SIGSEGV in QMutex::lock()

Binary package hint: kdebase-runtime

crashes on reboot

ProblemType: Crash
DistroRelease: Ubuntu 10.04
Package: kdebase-runtime 4:4.4.2-0ubuntu3
ProcVersionSignature: Ubuntu 2.6.32-20.30-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-20-generic x86_64
NonfreeKernelModules: fglrx
Architecture: amd64
Date: Wed Apr 14 16:53:34 2010
ExecutablePath: /usr/bin/nepomukservicestub
InstallationMedia: Kubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100414)
ProcCmdline: /usr/bin/nepomukservicestub nepomukremovablestorageservice
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
 LANGUAGE=
SegvAnalysis:
 Segfault happened at: 0x7fd18a8e08dc <_ZN6QMutex4lockEv+12>: cmpb $0x0,(%rdx)
 PC (0x7fd18a8e08dc) ok
 source "$0x0" ok
 destination "(%rdx)" (0x00000000) not located in a known VMA region (needed writable region)!
SegvReason: writing NULL VMA
Signal: 11
SourcePackage: kdebase-runtime
StacktraceTop:
 QMutex::lock() () from /usr/lib/libQtCore.so.4
 ?? () from /usr/lib/libsopranoclient.so.1
 QThreadStorageData::set(void*) ()
 ?? () from /usr/lib/libQtGui.so.4
 QApplication::~QApplication() ()
Title: nepomukservicestub crashed with SIGSEGV in QMutex::lock()
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
XsessionErrors: (process:2214): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed