Version:           3.5.7 (using KDE 3.5.7 "release 64.1" , openSUSE )
Compiler:          Target: i586-suse-linux
OS:                Linux (i686) release 2.6.16.27-0.9-default

Suddenly Kontact refused to start any more showing the following backtrace (reboot does not help):
Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1241045328 (LWP 6205)]
[KCrash handler]
#6  0xffffffcc in ?? ()
#7  0xb7e0a072 in Kontact::Plugin::part ()
   from /opt/kde3/lib/libkpinterfaces.so.1
#8  0x0805bef0 in Kontact::MainWindow::selectPlugin ()
#9  0x08059ad2 in Kontact::MainWindow::loadSettings ()
#10 0x0805d912 in Kontact::MainWindow::initObject ()
#11 0x0805866f in KontactApp::newInstance ()
#12 0xb726baad in KUniqueApplication::processDelayed ()
   from /opt/kde3/lib/libkdecore.so.4
#13 0xb729bdc8 in KUniqueApplication::qt_invoke ()
   from /opt/kde3/lib/libkdecore.so.4
#14 0xb6c7614d in QObject::activate_signal ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#15 0xb6fb02fe in QSignal::signal () from /usr/lib/qt3/lib/libqt-mt.so.3
#16 0xb6c92207 in QSignal::activate () from /usr/lib/qt3/lib/libqt-mt.so.3
#17 0xb6c995c3 in QSingleShotTimer::event ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#18 0xb6c16bb7 in QApplication::internalNotify ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#19 0xb6c17981 in QApplication::notify () from /usr/lib/qt3/lib/libqt-mt.so.3
#20 0xb72cc433 in KApplication::notify () from /opt/kde3/lib/libkdecore.so.4
#21 0xb6c0bd56 in QEventLoop::activateTimers ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#22 0xb6bc5b00 in QEventLoop::processEvents ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#23 0xb6c2d9d8 in QEventLoop::enterLoop () from /usr/lib/qt3/lib/libqt-mt.so.3
#24 0xb6c2d86e in QEventLoop::exec () from /usr/lib/qt3/lib/libqt-mt.so.3
#25 0xb6c1676f in QApplication::exec () from /usr/lib/qt3/lib/libqt-mt.so.3
#26 0x08058c39 in main ()


This is kontacts backtrace when started from a freshly created new user account:
Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1240582480 (LWP 9068)]
[New Thread -1286034528 (LWP 9294)]
[New Thread -1277641824 (LWP 9293)]
[New Thread -1269249120 (LWP 9292)]
[New Thread -1260856416 (LWP 9291)]
[KCrash handler]
#6  0xffffffcc in ?? ()
#7  0xb7e7b072 in Kontact::Plugin::part ()
   from /opt/kde3/lib/libkpinterfaces.so.1
#8  0x0805bef0 in Kontact::MainWindow::selectPlugin ()
#9  0x08059ad2 in Kontact::MainWindow::loadSettings ()
#10 0x0805d912 in Kontact::MainWindow::initObject ()
#11 0x0805866f in KontactApp::newInstance ()
#12 0xb72dcaad in KUniqueApplication::processDelayed ()
   from /opt/kde3/lib/libkdecore.so.4
#13 0xb730cdc8 in KUniqueApplication::qt_invoke ()
   from /opt/kde3/lib/libkdecore.so.4
#14 0xb6ce714d in QObject::activate_signal ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#15 0xb70212fe in QSignal::signal () from /usr/lib/qt3/lib/libqt-mt.so.3
#16 0xb6d03207 in QSignal::activate () from /usr/lib/qt3/lib/libqt-mt.so.3
#17 0xb6d0a5c3 in QSingleShotTimer::event ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#18 0xb6c87bb7 in QApplication::internalNotify ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#19 0xb6c88981 in QApplication::notify () from /usr/lib/qt3/lib/libqt-mt.so.3
#20 0xb733d433 in KApplication::notify () from /opt/kde3/lib/libkdecore.so.4
#21 0xb6c7cd56 in QEventLoop::activateTimers ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#22 0xb6c36b00 in QEventLoop::processEvents ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#23 0xb6c9e9d8 in QEventLoop::enterLoop () from /usr/lib/qt3/lib/libqt-mt.so.3
#24 0xb6c9e86e in QEventLoop::exec () from /usr/lib/qt3/lib/libqt-mt.so.3
#25 0xb6c8776f in QApplication::exec () from /usr/lib/qt3/lib/libqt-mt.so.3
#26 0x08058c39 in main ()