Application that crashed: kmail
Version of the application: 1.12.0
KDE Version: 4.2.96 (KDE 4.2.96 (KDE 4.3 RC2))
Qt Version: 4.5.2
Operating System: Linux 2.6.31-3-generic x86_64
Distribution: Ubuntu karmic (development branch)

What I was doing when the application crashed:
Happens on each initil kmail startup after a system reboot. After kmail crashed once, it doesn't happen again.

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f62cd6c1750 (LWP 5003))]

Thread 3 (Thread 0x7f62aeecc950 (LWP 5034)):
#0  pthread_cond_timedwait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:217
#1  0x00007f62cadd0402 in QWaitConditionPrivate::wait (this=<value optimized out>, mutex=0x29f6730, time=30000) at thread/qwaitcondition_unix.cpp:85
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x29f6730, time=30000) at thread/qwaitcondition_unix.cpp:159
#3  0x00007f62cadc6492 in QThreadPoolThread::run (this=<value optimized out>) at concurrent/qthreadpool.cpp:140
#4  0x00007f62cadcf3e5 in QThreadPrivate::start (arg=0x2b39f50) at thread/qthread_unix.cpp:188
#5  0x00007f62c59113aa in start_thread (arg=<value optimized out>) at pthread_create.c:300
#6  0x00007f62ca5bcf6d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f62ae6cb950 (LWP 5035)):
#0  pthread_cond_timedwait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:217
#1  0x00007f62cadd0402 in QWaitConditionPrivate::wait (this=<value optimized out>, mutex=0x29f6730, time=30000) at thread/qwaitcondition_unix.cpp:85
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x29f6730, time=30000) at thread/qwaitcondition_unix.cpp:159
#3  0x00007f62cadc6492 in QThreadPoolThread::run (this=<value optimized out>) at concurrent/qthreadpool.cpp:140
#4  0x00007f62cadcf3e5 in QThreadPrivate::start (arg=0x2bfef60) at thread/qthread_unix.cpp:188
#5  0x00007f62c59113aa in start_thread (arg=<value optimized out>) at pthread_create.c:300
#6  0x00007f62ca5bcf6d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f62cd6c1750 (LWP 5003)):
[KCrash Handler]
#5  DwEntity::Headers (this=0x0) at ../../mimelib/entity.cpp:242
#6  0x00007f62cc198b00 in KMMessage::headerField (this=0x2bf90c0, aName=..., encodingMode=KMMessage::MessageCharsetEncoding) at ../../kmail/kmmessage.cpp:1989
#7  0x00007f62cc3e9426 in KMail::FancyHeaderStyle::format (this=<value optimized out>, message=<value optimized out>, strategy=<value optimized out>, vCardName=<value optimized out>, 
    printing=<value optimized out>, topLevel=true) at ../../kmail/headerstyle.cpp:499
#8  0x00007f62cc28a204 in KMReaderWin::writeMsgHeader (this=0x1bec0a0, aMsg=<value optimized out>, hasVCard=false, topLevel=<value optimized out>) at ../../kmail/kmreaderwin.cpp:1767
#9  0x00007f62cc290818 in KMReaderWin::parseMsg (this=0x1bec0a0, aMsg=0x2bf90c0) at ../../kmail/kmreaderwin.cpp:1652
#10 0x00007f62cc28002a in KMReaderWin::displayMessage (this=0x1bec0a0) at ../../kmail/kmreaderwin.cpp:1589
#11 0x00007f62cc280204 in KMReaderWin::updateReaderWin (this=0x1bec0a0) at ../../kmail/kmreaderwin.cpp:1529
#12 0x00007f62cc28be3d in KMReaderWin::qt_metacall (this=0x1bec0a0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff38427760) at ./kmreaderwin.moc:165
#13 0x00007f62caecae1c in QMetaObject::activate (sender=0x1bec138, from_signal_index=<value optimized out>, to_signal_index=<value optimized out>, argv=0x1) at kernel/qobject.cpp:3113
#14 0x00007f62caec4dc3 in QObject::event (this=0x1bec138, e=0x2bf90c0) at kernel/qobject.cpp:1075
#15 0x00007f62cb34862c in QApplicationPrivate::notify_helper (this=0x16b81f0, receiver=0x1bec138, e=0x7fff38427d60) at kernel/qapplication.cpp:4056
#16 0x00007f62cb34f8fe in QApplication::notify (this=0x7fff384281b0, receiver=0x1bec138, e=0x7fff38427d60) at kernel/qapplication.cpp:4021
#17 0x00007f62cd0fb446 in KApplication::notify (this=0x7fff384281b0, receiver=0x1bec138, event=0x7fff38427d60) at ../../kdeui/kernel/kapplication.cpp:302
#18 0x00007f62caeb5c6c in QCoreApplication::notifyInternal (this=0x7fff384281b0, receiver=0x1bec138, event=0x7fff38427d60) at kernel/qcoreapplication.cpp:610
#19 0x00007f62caee0912 in QCoreApplication::sendEvent (this=0x165acd0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#20 QTimerInfoList::activateTimers (this=0x165acd0) at kernel/qeventdispatcher_unix.cpp:572
#21 0x00007f62caede2ad in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:165
#22 0x00007f62c258b9fe in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#23 0x00007f62c258f3c8 in ?? () from /usr/lib/libglib-2.0.so.0
#24 0x00007f62c258f4f0 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#25 0x00007f62caede1f6 in QEventDispatcherGlib::processEvents (this=0x161c6e0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:327
#26 0x00007f62cb3dcace in QGuiEventDispatcherGlib::processEvents (this=0x0, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#27 0x00007f62caeb4572 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#28 0x00007f62caeb4944 in QEventLoop::exec (this=0x7fff38428000, flags=) at kernel/qeventloop.cpp:201
#29 0x00007f62caeb6af9 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#30 0x0000000000402fc9 in main (argc=<value optimized out>, argv=<value optimized out>) at ../../kmail/main.cpp:146

Reported using DrKonqi