Application: kmail (1.13.6)
KDE Platform Version: 4.6.00 (4.6.0) "release 6"
Qt Version: 4.7.1
Operating System: Linux 2.6.37.6-0.5-desktop x86_64
Distribution: "openSUSE 11.4 (x86_64)"

-- Information about the crash:
- What I was doing when the application crashed:
Initiated a search ("Find Messages") on INBOX with key string "anywhere in headers"
Pop-up asked whether OK to download all messages from IMAP Server - Yes.
Cancelled search after some results found.
Tried simpler search on From: only - no results shown
Cancelled this search too and tried another - still no results although there should have been matches (search was not actually being run as previous operation was still queued).
Closed search window and returned to main window
Selected several messages and marked them as read and dragged them to another folder
This didn't appear to do anything, so I checked the ongoing-operations status.
The first operation shown was "21% of messages downloaded" (from the original search) so I cancelled it.
I may have then clicked on another message in the message-list pane, or maybe not.
At this poijnt, KMail crashed.
Backtrace suggests it was trying to assign a task to a KIO slave that no longer exists.

-- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
82	T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
[Current thread is 1 (Thread 0x7f9bc8bcc760 (LWP 31199))]

Thread 2 (Thread 0x7f9ba62d5700 (LWP 328)):
#0  0x00007f9bc57ae503 in __poll (fds=<value optimized out>, nfds=<value optimized out>, timeout=<value optimized out>) at ../sysdeps/unix/sysv/linux/poll.c:87
#1  0x00007f9bbd2da114 in g_main_context_poll (context=0x4cbbda0, block=1, dispatch=1, self=<value optimized out>) at gmain.c:3404
#2  g_main_context_iterate (context=0x4cbbda0, block=1, dispatch=1, self=<value optimized out>) at gmain.c:3086
#3  0x00007f9bbd2da650 in g_main_context_iteration (context=0x4cbbda0, may_block=1) at gmain.c:3154
#4  0x00007f9bc60fc976 in QEventDispatcherGlib::processEvents (this=0x74cb520, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:424
#5  0x00007f9bc60d1052 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007f9bc60d1265 in QEventLoop::exec (this=0x7f9ba62d4de0, flags=...) at kernel/qeventloop.cpp:201
#7  0x00007f9bc5fe61e4 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:490
#8  0x00007f9bc60b2968 in QInotifyFileSystemWatcherEngine::run (this=0x4f95950) at io/qfilesystemwatcher_inotify.cpp:248
#9  0x00007f9bc5fe8a5e in QThreadPrivate::start (arg=0x4f95950) at thread/qthread_unix.cpp:285
#10 0x00007f9bc364ea3f in start_thread (arg=0x7f9ba62d5700) at pthread_create.c:297
#11 0x00007f9bc57b767d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#12 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f9bc8bcc760 (LWP 31199)):
[KCrash Handler]
#6  QString (this=0x0) at /usr/include/QtCore/qstring.h:728
#7  KIO::Slave::protocol (this=0x0) at /usr/src/debug/kdelibs-4.6.0/kio/kio/slave.cpp:182
#8  0x00007f9bc2685109 in KIO::SchedulerPrivate::assignJobToSlave (this=0x1141450, slave=0x0, job=0x49fb680) at /usr/src/debug/kdelibs-4.6.0/kio/kio/scheduler.cpp:1230
#9  0x00007f9bc7892a6b in KMail::SearchJob::searchSingleMessage (this=0x7c34a00) at /usr/src/debug/kdepim-4.4.10/kmail/searchjob.cpp:395
#10 0x00007f9bc78083f4 in KMFolderSearch::propagateHeaderChanged (this=0xc9d070, aFolder=0x992bf0, idx=<value optimized out>) at /usr/src/debug/kdepim-4.4.10/kmail/kmfoldersearch.cpp:1167
#11 0x00007f9bc7809d25 in KMFolderSearch::qt_metacall (this=0xc9d070, _c=QMetaObject::InvokeMetaMethod, _id=8, _a=0x7ffff984aef0) at /usr/src/debug/kdepim-4.4.10/build/kmail/kmfoldersearch.moc:193
#12 0x00007f9bc60e6def in QMetaObject::activate (sender=0x96a210, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x7ffff984aef0) at kernel/qobject.cpp:3272
#13 0x00007f9bc76790c0 in KMFolderMgr::msgHeaderChanged (this=<value optimized out>, _t1=0x992bf0, _t2=169) at /usr/src/debug/kdepim-4.4.10/build/kmail/kmfoldermgr.moc:169
#14 0x00007f9bc767ae29 in KMFolderMgr::qt_metacall (this=0x96a210, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7ffff984b020) at /usr/src/debug/kdepim-4.4.10/build/kmail/kmfoldermgr.moc:104
#15 0x00007f9bc60e6def in QMetaObject::activate (sender=0x992bf0, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x7ffff984b020) at kernel/qobject.cpp:3272
#16 0x00007f9bc762e430 in KMFolder::msgHeaderChanged (this=<value optimized out>, _t1=0x992bf0, _t2=169) at /usr/src/debug/kdepim-4.4.10/build/kmail/kmfolder.moc:258
#17 0x00007f9bc762fd77 in KMFolder::qt_metacall (this=0x992bf0, _c=QMetaObject::InvokeMetaMethod, _id=14, _a=0x7ffff984b150) at /usr/src/debug/kdepim-4.4.10/build/kmail/kmfolder.moc:137
#18 0x00007f9bc60e6def in QMetaObject::activate (sender=0x995670, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x7ffff984b150) at kernel/qobject.cpp:3272
#19 0x00007f9bc7655fb0 in FolderStorage::msgHeaderChanged (this=<value optimized out>, _t1=0x992bf0, _t2=169) at /usr/src/debug/kdepim-4.4.10/build/kmail/folderstorage.moc:280
#20 0x00007f9bc764bc32 in KMReaderWin::parseMsg (this=0x8e4520, aMsg=0x4a5fa10) at /usr/src/debug/kdepim-4.4.10/kmail/kmreaderwin.cpp:1623
#21 0x00007f9bc764a670 in KMReaderWin::displayMessage (this=0x8e4520) at /usr/src/debug/kdepim-4.4.10/kmail/kmreaderwin.cpp:1536
#22 0x00007f9bc764a841 in KMReaderWin::updateReaderWin (this=0x8e4520) at /usr/src/debug/kdepim-4.4.10/kmail/kmreaderwin.cpp:1479
#23 0x00007f9bc764e260 in KMReaderWin::qt_metacall (this=0x8e4520, _c=QMetaObject::InvokeMetaMethod, _id=6, _a=0x7ffff984b930) at /usr/src/debug/kdepim-4.4.10/build/kmail/kmreaderwin.moc:179
#24 0x00007f9bc60e6def in QMetaObject::activate (sender=0x8e45c8, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x0) at kernel/qobject.cpp:3272
#25 0x00007f9bc60e5799 in QObject::event (this=0x8e45c8, e=<value optimized out>) at kernel/qobject.cpp:1175
#26 0x00007f9bc65cfd14 in QApplicationPrivate::notify_helper (this=0x66ba60, receiver=0x8e45c8, e=0x7ffff984c0d0) at kernel/qapplication.cpp:4445
#27 0x00007f9bc65d822a in QApplication::notify (this=<value optimized out>, receiver=0x8e45c8, e=0x7ffff984c0d0) at kernel/qapplication.cpp:4324
#28 0x00007f9bc85599e6 in KApplication::notify (this=0x7ffff984c5b0, receiver=0x8e45c8, event=0x7ffff984c0d0) at /usr/src/debug/kdelibs-4.6.0/kdeui/kernel/kapplication.cpp:311
#29 0x00007f9bc60d1bfc in QCoreApplication::notifyInternal (this=0x7ffff984c5b0, receiver=0x8e45c8, event=0x7ffff984c0d0) at kernel/qcoreapplication.cpp:732
#30 0x00007f9bc60ff4d8 in sendEvent (this=0x66f4f0) at kernel/qcoreapplication.h:215
#31 QTimerInfoList::activateTimers (this=0x66f4f0) at kernel/qeventdispatcher_unix.cpp:618
#32 0x00007f9bc60fc244 in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#33 0x00007f9bbd2d9bd3 in g_main_dispatch (context=0x66e4e0) at gmain.c:2440
#34 g_main_context_dispatch (context=0x66e4e0) at gmain.c:3013
#35 0x00007f9bbd2da3b0 in g_main_context_iterate (context=0x66e4e0, block=1, dispatch=1, self=<value optimized out>) at gmain.c:3091
#36 0x00007f9bbd2da650 in g_main_context_iteration (context=0x66e4e0, may_block=1) at gmain.c:3154
#37 0x00007f9bc60fc91f in QEventDispatcherGlib::processEvents (this=0x6125e0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#38 0x00007f9bc6674d8e in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#39 0x00007f9bc60d1052 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#40 0x00007f9bc60d1265 in QEventLoop::exec (this=0x7ffff984c3e0, flags=...) at kernel/qeventloop.cpp:201
#41 0x00007f9bc60d56ab in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1009
#42 0x00000000004033e8 in main (argc=<value optimized out>, argv=<value optimized out>) at /usr/src/debug/kdepim-4.4.10/kmail/main.cpp:156

Reported using DrKonqi