Application: kmail (4.10 beta2)
KDE Platform Version: 4.9.80 (Compiled from sources)
Qt Version: 4.8.2
Operating System: Linux 3.2.0-4-amd64 x86_64
Distribution: Debian GNU/Linux unstable (sid)

-- Information about the crash:
- What I was doing when the application crashed:
I received an invitation for a meeting by email a couple of days ago
Accepted it
Today, I received an email informing me that the meeting has been canceled
KMail had a button to revoke/remove the item from my calendar
I clicked on it
First I got an alert telling me that no item has been found
When I clicked ok, KMail crashed.

-- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f829f1e07a0 (LWP 16621))]

Thread 3 (Thread 0x7f827b117700 (LWP 16624)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f8291644c0d in ?? () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#2  0x00007f8291644d19 in ?? () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#3  0x00007f828c14f2e4 in ?? () from /usr/lib/x86_64-linux-gnu/libGL.so.1
#4  0x00007f8299700b50 in start_thread (arg=<optimized out>) at pthread_create.c:304
#5  0x00007f829870babd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f827a7ee700 (LWP 16625)):
#0  0x00007f8298700e73 in *__GI___poll (fds=<optimized out>, nfds=<optimized out>, timeout=9791) at ../sysdeps/unix/sysv/linux/poll.c:87
#1  0x00007f828d8c6624 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f828d8c6744 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f8299ac1296 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#4  0x00007f8299a918af in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#5  0x00007f8299a91b38 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#6  0x00007f8299994d70 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#7  0x00007f8299997d0b in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#8  0x00007f828c14f2e4 in ?? () from /usr/lib/x86_64-linux-gnu/libGL.so.1
#9  0x00007f8299700b50 in start_thread (arg=<optimized out>) at pthread_create.c:304
#10 0x00007f829870babd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f829f1e07a0 (LWP 16621)):
[KCrash Handler]
#6  CalendarSupport::NepomukCalendar::weakPointer (this=0x0) at /home/emilsedgh/kde/sc/kdepim/calendarsupport/nepomukcalendar.cpp:416
#7  0x00007f8285286394 in CalendarSupport::Groupware::calendarJobFinished (this=0x3f25b30, success=true, errorString=...) at /home/emilsedgh/kde/sc/kdepim/calendarsupport/groupware.cpp:484
#8  0x00007f8299aa7a2e in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#9  0x00007f829a49c70c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#10 0x00007f829a4a0b8a in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#11 0x00007f829ebed946 in KApplication::notify (this=0x7fff603e9fb0, receiver=0x3f25b30, event=0x5829fc0) at /home/emilsedgh/kde/sc/kdelibs/kdeui/kernel/kapplication.cpp:311
#12 0x00007f8299a92b5e in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#13 0x00007f8299a969e1 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#14 0x00007f8299ac10e3 in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#15 0x00007f828d8c6355 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#16 0x00007f828d8c6688 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#17 0x00007f828d8c6744 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007f8299ac1276 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#19 0x00007f829a53d83e in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#20 0x00007f8299a918af in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#21 0x00007f8299a91b38 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#22 0x00007f8299a96cf8 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#23 0x000000000040308c in main (argc=<optimized out>, argv=<optimized out>) at /home/emilsedgh/kde/sc/kdepim/kmail/main.cpp:148

Reported using DrKonqi