Application that crashed: kontact
Version of the application: 4.3.1
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.2
Operating System: Linux 2.6.30-1-686 i686
Distribution: Debian GNU/Linux testing (squeeze)

What I was doing when the application crashed:
When I do generic searches in local scope, kontact usually crashed.
I guest It could be when kontact returns too many results.
I search through "Find Messages" -> "Search in all local folders" -> "March all of the following".

I think my mailbox isn't too big anyway:
bpk@osaka ~ $ du -sh .kde/share/apps/kmail/
287M    .kde/share/apps/kmail/


 -- Backtrace:
Application: Kontact (kontact), signal: Segmentation fault
[Current thread is 1 (Thread 0xb4879700 (LWP 1616))]

Thread 2 (Thread 0xafd91b90 (LWP 10816)):
#0  0xb7fa7424 in __kernel_vsyscall ()
#1  0xb5194292 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/i686/cmov/libpthread.so.0
#2  0xb6b1f8b4 in pthread_cond_timedwait () from /lib/i686/cmov/libc.so.6
#3  0xb769353c in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQtCore.so.4
#4  0xb7688d3e in ?? () from /usr/lib/libQtCore.so.4
#5  0xb7692582 in ?? () from /usr/lib/libQtCore.so.4
#6  0xb51904b5 in start_thread () from /lib/i686/cmov/libpthread.so.0
#7  0xb6b10a5e in clone () from /lib/i686/cmov/libc.so.6

Thread 1 (Thread 0xb4879700 (LWP 1616)):
[KCrash Handler]
#6  0xb15a1613 in ?? () from /usr/lib/libkmailprivate.so.4
#7  0xb1599ef6 in ?? () from /usr/lib/libkmailprivate.so.4
#8  0xb144f1e7 in KMMainWidget::updateMessageActions() () from /usr/lib/libkmailprivate.so.4
#9  0xb1469ff1 in KMMainWidget::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libkmailprivate.so.4
#10 0xb7798b33 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQtCore.so.4
#11 0xb7799782 in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/libQtCore.so.4
#12 0xb77d4177 in QTimer::timeout() () from /usr/lib/libQtCore.so.4
#13 0xb779ee9e in QTimer::timerEvent(QTimerEvent*) () from /usr/lib/libQtCore.so.4
#14 0xb7793bcf in QObject::event(QEvent*) () from /usr/lib/libQtCore.so.4
#15 0xb6dc3814 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#16 0xb6dcb97e in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#17 0xb7c844ad in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#18 0xb77839cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#19 0xb77b2361 in ?? () from /usr/lib/libQtCore.so.4
#20 0xb77ae900 in ?? () from /usr/lib/libQtCore.so.4
#21 0xb51dde98 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#22 0xb51e1623 in ?? () from /lib/libglib-2.0.so.0
#23 0xb51e17a8 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#24 0xb77ae858 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#25 0xb6e62fd5 in ?? () from /usr/lib/libQtGui.so.4
#26 0xb778201a in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#27 0xb7782462 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#28 0xb77848b9 in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#29 0xb6dc3697 in QApplication::exec() () from /usr/lib/libQtGui.so.4
#30 0x0804bd40 in _start ()

Reported using DrKonqi