Application that crashed: kmail
Version of the application: 1.11.90
KDE Version: 4.2.91 (KDE 4.2.91 (KDE 4.3 >= 20090609))
Qt Version: 4.5.1
Operating System: Linux 2.6.29-gentoo-r5 x86_64

What I was doing when the application crashed:
kmail (reproducibly) crashes after selecting one of the incoming spams

it looks somehow similar to bug 180741, but I'm really not sure if it the same

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#4  0x00000039a8570c5b in KMail::ObjectTreeParser::defaultHandling (this=<value optimized out>, node=<value optimized out>, result=<value optimized out>)
    at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91/kmail/objecttreeparser.cpp:313
#5  0x00000039a857164d in KMail::ObjectTreeParser::parseObjectTree (this=<value optimized out>, node=<value optimized out>)
    at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91/kmail/objecttreeparser.cpp:291
#6  0x00000039a83f260a in KMReaderWin::parseMsg (this=<value optimized out>, aMsg=<value optimized out>) at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91/kmail/kmreaderwin.cpp:1656
#7  0x00000039a83df23a in KMReaderWin::displayMessage (this=<value optimized out>) at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91/kmail/kmreaderwin.cpp:1589
#8  0x00000039a83df425 in KMReaderWin::updateReaderWin (this=<value optimized out>) at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91/kmail/kmreaderwin.cpp:1529
#9  0x00000039a83edb75 in KMReaderWin::qt_metacall (this=<value optimized out>, _c=<value optimized out>, _id=<value optimized out>, _a=<value optimized out>)
    at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91_build/kmail/kmreaderwin.moc:165
#10 0x000000351553fde5 in QMetaObject::activate (sender=<value optimized out>, from_signal_index=<value optimized out>, to_signal_index=<value optimized out>, argv=<value optimized out>)
    at kernel/qobject.cpp:3108
#11 0x000000351553c513 in QObject::event (this=<value optimized out>, e=<value optimized out>) at kernel/qobject.cpp:1073
#12 0x000000352099c8dd in QApplicationPrivate::notify_helper (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:4057
#13 0x00000035209a51aa in QApplication::notify (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:4022
#14 0x00000039a001a4db in KApplication::notify (this=<value optimized out>, receiver=<value optimized out>, event=<value optimized out>)
    at /var/tmp/portage/kde-base/kdelibs-4.2.91/work/kdelibs-4.2.91/kdeui/kernel/kapplication.cpp:302
#15 0x000000351552dbf3 in QCoreApplication::notifyInternal (this=<value optimized out>, receiver=<value optimized out>, event=<value optimized out>) at kernel/qcoreapplication.cpp:606
#16 0x0000003515555a7e in QTimerInfoList::activateTimers (this=<value optimized out>) at kernel/qcoreapplication.h:213
#17 0x0000003515552bbd in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:164
#18 0x00000035148397c1 in IA__g_main_context_dispatch (context=<value optimized out>) at gmain.c:1814
#19 0x000000351483cd98 in g_main_context_iterate (context=<value optimized out>, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>) at gmain.c:2445
#20 0x000000351483cf5c in IA__g_main_context_iteration (context=<value optimized out>, may_block=<value optimized out>) at gmain.c:2508
#21 0x0000003515552b2f in QEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:324
#22 0x0000003520a21b1f in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#23 0x000000351552c5f2 in QEventLoop::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventloop.cpp:149
#24 0x000000351552c785 in QEventLoop::exec (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventloop.cpp:196
#25 0x000000351552e784 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#26 0x000000000040333b in main (argc=<value optimized out>, argv=<value optimized out>) at /var/tmp/portage/kde-base/kmail-4.2.91/work/kmail-4.2.91/kmail/main.cpp:146

Reported using DrKonqi