Application that crashed: kontact
Version of the application: 4.3.0 pre
KDE Version: 4.2.85 (KDE 4.2.85 (KDE 4.3 Beta1))
Qt Version: 4.5.1
Operating System: Linux 2.6.28-gentoo-r5 x86_64

What I was doing when the application crashed:
I just started up kontact, and saw a message as spam, so I hit the special key on my keyboard I've assigned to "mark as spam", and, after what seemed like a hang, it died.  (It very well could have been trying to retrieve mail from local, POP, and/or IMAP at the same time, so any of those could have been related.)

 -- Backtrace:
Application: Kontact (kontact), signal: Segmentation fault
[KCrash Handler]
#5  0x0000000002492ae0 in ?? ()
#6  0x00007fdf865fa2d3 in KMCommand::slotStart () from /usr/kde/4.3/lib64/libkmailprivate.so.4
#7  0x00007fdf865e9ab2 in KMCommand::qt_metacall () from /usr/kde/4.3/lib64/libkmailprivate.so.4
#8  0x00007fdf98c7a6c8 in QMetaObject::activate (sender=0x29141a0, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x1) at kernel/qobject.cpp:3108
#9  0x00007fdf98c800bf in QSingleShotTimer::timerEvent (this=0x29141a0) at kernel/qtimer.cpp:298
#10 0x00007fdf98c7506b in QObject::event (this=0x29141a0, e=0x2d27620) at kernel/qobject.cpp:1073
#11 0x00007fdf997f2bbd in QApplicationPrivate::notify_helper (this=0x15ceea0, receiver=0x29141a0, e=0x7fffa6e2dc40) at kernel/qapplication.cpp:4057
#12 0x00007fdf997fb3de in QApplication::notify (this=0x7fffa6e2e090, receiver=0x29141a0, e=0x7fffa6e2dc40) at kernel/qapplication.cpp:4022
#13 0x00007fdf9a66ec8a in KApplication::notify () from /usr/kde/4.3/lib64/libkdeui.so.5
#14 0x00007fdf98c64fcb in QCoreApplication::notifyInternal (this=0x7fffa6e2e090, receiver=0x29141a0, event=0x7fffa6e2dc40) at kernel/qcoreapplication.cpp:606
#15 0x00007fdf98c904fe in QTimerInfoList::activateTimers (this=0x15ccf10) at kernel/qcoreapplication.h:213
#16 0x00007fdf98c8d0ad in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:164
#17 0x00007fdf93dd83d4 in g_main_dispatch () from /usr/lib/libglib-2.0.so.0
#18 0x00007fdf93dda165 in g_main_context_iterate () from /usr/lib/libglib-2.0.so.0
#19 0x00007fdf93dda33d in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#20 0x00007fdf98c8d00f in QEventDispatcherGlib::processEvents (this=0x15a1950, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:324
#21 0x00007fdf99880808 in QGuiEventDispatcherGlib::processEvents (this=0x33c6920, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#22 0x00007fdf98c63bf2 in QEventLoop::processEvents (this=<value optimized out>, flags={i = -1495081296}) at kernel/qeventloop.cpp:149
#23 0x00007fdf98c63d95 in QEventLoop::exec (this=0x7fffa6e2def0, flags={i = -1495081216}) at kernel/qeventloop.cpp:196
#24 0x00007fdf98c6895e in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#25 0x0000000000404dec in main ()