Version:            (using KDE KDE 3.2.2)
Installed from:    Gentoo Packages
Compiler:          gcc (GCC) 3.3.2 20031218 (Gentoo Linux 3.3.2-r5, propolice-3.3-7) 
OS:                Linux

The crash happens most often when I am applying filters on a large (20+) messages. Like in the morning after messages from mailing lists have been accumulating over night. However that might be because there is something about some particular message which upsets things, and it is just more likely that one of those messages is in a large group of messages. I tried applying the filter to each message individually and got several more crashes, but then kmail seamed to fix itself and filtered properly, so I wasn't able to tie it down to a particular message. Below is the backtrace:

Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 16384 (LWP 4658)]
0x41d807e8 in waitpid () from /lib/libpthread.so.0
#0  0x41d807e8 in waitpid () from /lib/libpthread.so.0
#1  0x4137fc34 in __JCR_LIST__ () from /usr/kde/3.2/lib/libkdecore.so.4
#2  0x412be513 in KCrash::defaultCrashHandler(int) ()
   from /usr/kde/3.2/lib/libkdecore.so.4
#3  0x41d7f4d3 in __pthread_sighandler () from /lib/libpthread.so.0
#4  <signal handler called>
#5  0x401a9df9 in KMHeaders::msgRemoved(int, QString, QString) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#6  0x401b3f58 in KMHeaders::qt_invoke(int, QUObject*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#7  0x4168123c in QObject::activate_signal(QConnectionList*, QUObject*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#8  0x401e79e3 in KMFolder::msgRemoved(int, QString, QString) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#9  0x401e4835 in KMFolder::take(int) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#10 0x4027f38d in KMFolderImap::take(int) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#11 0x40296da1 in KMFolderMaildir::addMsg(KMMessage*, int*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#12 0x401e4e58 in KMFolder::moveMsg(KMMessage*, int*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#13 0x4022da2f in KMFilterMgr::process(KMMessage*, KMFilterMgr::FilterSet) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#14 0x401aaa2e in KMHeaders::slotFilterMsg(KMMessage*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#15 0x401b410d in KMHeaders::qt_invoke(int, QUObject*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#16 0x4168123c in QObject::activate_signal(QConnectionList*, QUObject*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#17 0x4032a868 in KMail::FolderJob::messageRetrieved(KMMessage*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#18 0x40334d17 in KMail::ImapJob::slotGetMessageResult(KIO::Job*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#19 0x403365a0 in KMail::ImapJob::qt_invoke(int, QUObject*) ()
   from /usr/kde/3.2/lib/libkmailprivate.so.0
#20 0x4168123c in QObject::activate_signal(QConnectionList*, QUObject*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#21 0x40d19708 in KIO::Job::result(KIO::Job*) ()
   from /usr/kde/3.2/lib/libkio.so.4
#22 0x40d04ccf in KIO::Job::emitResult() () from /usr/kde/3.2/lib/libkio.so.4
#23 0x40d0613e in KIO::SimpleJob::slotFinished() ()
   from /usr/kde/3.2/lib/libkio.so.4
#24 0x40d08d5f in KIO::TransferJob::slotFinished() ()
   from /usr/kde/3.2/lib/libkio.so.4
#25 0x40d1addb in KIO::TransferJob::qt_invoke(int, QUObject*) ()
   from /usr/kde/3.2/lib/libkio.so.4
#26 0x4168123c in QObject::activate_signal(QConnectionList*, QUObject*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#27 0x41681074 in QObject::activate_signal(int) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#28 0x40cf903e in KIO::SlaveInterface::finished() ()
   from /usr/kde/3.2/lib/libkio.so.4
#29 0x40cf7d0f in KIO::SlaveInterface::dispatch(int, QMemArray<char> const&) ()
   from /usr/kde/3.2/lib/libkio.so.4
#30 0x40cf72d9 in KIO::SlaveInterface::dispatch() ()
   from /usr/kde/3.2/lib/libkio.so.4
#31 0x40cf4d9b in KIO::Slave::gotInput() () from /usr/kde/3.2/lib/libkio.so.4
#32 0x40cf68a0 in KIO::Slave::qt_invoke(int, QUObject*) ()
   from /usr/kde/3.2/lib/libkio.so.4
#33 0x4168123c in QObject::activate_signal(QConnectionList*, QUObject*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#34 0x4168139d in QObject::activate_signal(int, int) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#35 0x419b1f12 in QSocketNotifier::activated(int) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#36 0x4169d500 in QSocketNotifier::event(QEvent*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#37 0x41625d2f in QApplication::internalNotify(QObject*, QEvent*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#38 0x416250fb in QApplication::notify(QObject*, QEvent*) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#39 0x4122af0c in KApplication::notify(QObject*, QEvent*) ()
   from /usr/kde/3.2/lib/libkdecore.so.4
#40 0x416157da in QEventLoop::activateSocketNotifiers() ()
   from /usr/qt/3/lib/libqt-mt.so.3
#41 0x415d13c1 in QEventLoop::processEvents(unsigned) ()
   from /usr/qt/3/lib/libqt-mt.so.3
#42 0x41637d48 in QEventLoop::enterLoop() () from /usr/qt/3/lib/libqt-mt.so.3
#43 0x41637bf8 in QEventLoop::exec() () from /usr/qt/3/lib/libqt-mt.so.3
#44 0x41625f81 in QApplication::exec() () from /usr/qt/3/lib/libqt-mt.so.3
#45 0x0804a572 in main ()