Application: kontact (4.8.0)
KDE Platform Version: 4.8.1 (4.8.1) "release 481"
Qt Version: 4.8.0
Operating System: Linux 3.2.7-10-desktop x86_64
Distribution: "openSUSE 12.1 (x86_64)"

-- Information about the crash:
- What I was doing when the application crashed:

Nothing special. I see these crashes since upgrading to KDE-4.8, KDE-4.8.1 did not fix it. 
KMail2 crashes after a while, between 1 to 5 minutes. Often it is not even a user action triggering the segfault, but "it just happens". 
I would call KMail2 currently very unstable because of this issue, I see about 10-20 crashes a day !

The crash can be reproduced some of the time.

-- Backtrace:
Application: Kontact (kontact), signal: Aborted
[Current thread is 1 (Thread 0x7f7855d51760 (LWP 6417))]

Thread 4 (Thread 0x7f783d31e700 (LWP 6418)):
#0  0x00007f784dbf3e6c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f7852582c12 in WTF::TCMalloc_PageHeap::scavengerThread (this=0x7f7852f211a0) at ../../../Source/JavaScriptCore/wtf/FastMalloc.cpp:2495
#2  0x00007f7852582c49 in WTF::TCMalloc_PageHeap::runScavengerThread (context=<optimized out>) at ../../../Source/JavaScriptCore/wtf/FastMalloc.cpp:1618
#3  0x00007f784dbeff05 in start_thread () from /lib64/libpthread.so.0
#4  0x00007f785327410d in clone () from /lib64/libc.so.6

Thread 3 (Thread 0x7f783ca05700 (LWP 6419)):
#0  0x00007fffe31ad8de in ?? ()
#1  0x00007f784b6cbd9a in clock_gettime () from /lib64/librt.so.1
#2  0x00007f785390ba24 in do_gettime (frac=0x7f783ca04bf8, sec=0x7f783ca04bf0) at tools/qelapsedtimer_unix.cpp:123
#3  qt_gettime () at tools/qelapsedtimer_unix.cpp:140
#4  0x00007f78539e20bd in QTimerInfoList::updateCurrentTime (this=0x7f78380020d0) at kernel/qeventdispatcher_unix.cpp:343
#5  0x00007f78539e1d71 in timerSourceCheckHelper (src=<optimized out>) at kernel/qeventdispatcher_glib.cpp:150
#6  timerSourceCheckHelper (src=<optimized out>) at kernel/qeventdispatcher_glib.cpp:144
#7  0x00007f784d6e0264 in g_main_context_check () from /usr/lib64/libglib-2.0.so.0
#8  0x00007f784d6e0ab2 in ?? () from /usr/lib64/libglib-2.0.so.0
#9  0x00007f784d6e0f59 in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#10 0x00007f78539e1956 in QEventDispatcherGlib::processEvents (this=0x7f78380008c0, flags=<optimized out>) at kernel/qeventdispatcher_glib.cpp:426
#11 0x00007f78539b1682 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#12 0x00007f78539b18d7 in QEventLoop::exec (this=0x7f783ca04e20, flags=...) at kernel/qeventloop.cpp:204
#13 0x00007f78538b2537 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:501
#14 0x00007f78538b555b in QThreadPrivate::start (arg=0x7a0780) at thread/qthread_unix.cpp:298
#15 0x00007f784dbeff05 in start_thread () from /lib64/libpthread.so.0
#16 0x00007f785327410d in clone () from /lib64/libc.so.6

Thread 2 (Thread 0x7f77edbe5700 (LWP 6543)):
[KCrash Handler]
#6  0x00007f78531cdd95 in raise () from /lib64/libc.so.6
#7  0x00007f78531cf2ab in abort () from /lib64/libc.so.6
#8  0x00007f7848a47655 in _dbus_abort () at dbus-sysdeps.c:94
#9  0x00007f7848a3e5f1 in _dbus_warn_check_failed (format=0x7f7848a4d920 "arguments to %s() were incorrect, assertion \"%s\" failed in file %s line %d.\nThis is normally a bug in some application using the D-Bus library.\n") at dbus-internals.c:289
#10 0x00007f78503ef10f in q_dbus_pending_call_unref (pending=<optimized out>) at qdbus_symbols_p.h:321
#11 QDBusPendingCallPrivate::~QDBusPendingCallPrivate (this=0x7f77e0010920, __in_chrg=<optimized out>) at qdbuspendingcall.cpp:137
#12 0x00007f78503ef2c3 in ~QExplicitlySharedDataPointer (this=<optimized out>, __in_chrg=<optimized out>) at ../../src/corelib/tools/qshareddata.h:166
#13 ~QDBusPendingCall (this=<optimized out>, __in_chrg=<optimized out>) at qdbuspendingcall.cpp:271
#14 QDBusPendingCall::~QDBusPendingCall (this=<optimized out>, __in_chrg=<optimized out>) at qdbuspendingcall.cpp:271
#15 0x00007f784b452ebd in ~QDBusPendingReply (this=0x7f77edbe4870, __in_chrg=<optimized out>) at /usr/include/QtDBus/qdbuspendingreply.h:115
#16 Nepomuk::ResourceWatcher::addResource (this=<optimized out>, res=<optimized out>) at /usr/src/debug/kdelibs-4.8.1/nepomuk/core/resourcewatcher.cpp:143
#17 0x00007f784b434dcb in Nepomuk::ResourceData::load (this=0x7f77e0002240) at /usr/src/debug/kdelibs-4.8.1/nepomuk/core/resourcedata.cpp:405
#18 0x00007f784b4357bc in Nepomuk::ResourceData::property (this=0x7f77e0002240, uri=...) at /usr/src/debug/kdelibs-4.8.1/nepomuk/core/resourcedata.cpp:265
#19 0x00007f784b44b7e3 in Nepomuk::Resource::property (this=0x7f77edbe4d20, uri=...) at /usr/src/debug/kdelibs-4.8.1/nepomuk/core/resource.cpp:301
#20 0x00007f77f39e40ca in MessageCore::NepomukResourceRetrieverRunnable::run (this=0x203a500) at /usr/src/debug/kdepim-4.8.1/messagecore/asyncnepomukresourceretriever.cpp:47
#21 0x00007f78538a8d12 in QThreadPoolThread::run (this=0x11f2bc0) at concurrent/qthreadpool.cpp:107
#22 0x00007f78538b555b in QThreadPrivate::start (arg=0x11f2bc0) at thread/qthread_unix.cpp:298
#23 0x00007f784dbeff05 in start_thread () from /lib64/libpthread.so.0
#24 0x00007f785327410d in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7f7855d51760 (LWP 6417)):
#0  0x00007f784dbf3e6c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f78538b5a6b in wait (time=18446744073709551615, this=0x11f1c80) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<optimized out>, mutex=0x11f1bb8, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:158
#3  0x00007f78538a849e in QThreadPoolPrivate::waitForDone (this=0x11f1b30, msecs=-1) at concurrent/qthreadpool.cpp:298
#4  0x00007f78538a9ec4 in QThreadPool::~QThreadPool (this=<optimized out>, __in_chrg=<optimized out>) at concurrent/qthreadpool.cpp:440
#5  0x00007f77f39e2a94 in ~AsyncNepomukResourceRetrieverPrivate (this=0x11e0420, __in_chrg=<optimized out>) at /usr/src/debug/kdepim-4.8.1/messagecore/asyncnepomukresourceretriever.cpp:58
#6  MessageCore::AsyncNepomukResourceRetriever::~AsyncNepomukResourceRetriever (this=0x11e00f0, __in_chrg=<optimized out>) at /usr/src/debug/kdepim-4.8.1/messagecore/asyncnepomukresourceretriever.cpp:113
#7  0x00007f77f3446b49 in ~CallbackNepomukResourceRetriever (this=0x11e00f0, __in_chrg=<optimized out>) at /usr/src/debug/kdepim-4.8.1/messagelist/core/callbacknepomukresourceretriever.h:32
#8  MessageList::CallbackNepomukResourceRetriever::~CallbackNepomukResourceRetriever (this=0x11e00f0, __in_chrg=<optimized out>) at /usr/src/debug/kdepim-4.8.1/messagelist/core/callbacknepomukresourceretriever.h:32
#9  0x00007f78531d09a1 in __run_exit_handlers () from /lib64/libc.so.6
#10 0x00007f78531d0a25 in exit () from /lib64/libc.so.6
#11 0x00007f7854431ae8 in qt_xio_errhandler () at kernel/qapplication_x11.cpp:770
#12 0x00007f7855108918 in KApplication::xioErrhandler (this=0x7fffe317dee0, dpy=0x65dd20) at /usr/src/debug/kdelibs-4.8.1/kdeui/kernel/kapplication.cpp:419
#13 0x00007f784f12e51e in _XIOError () from /usr/lib64/libX11.so.6
#14 0x00007f784f12be2d in _XEventsQueued () from /usr/lib64/libX11.so.6
#15 0x00007f784f11c81f in XEventsQueued () from /usr/lib64/libX11.so.6
#16 0x00007f785446911c in x11EventSourceCheck (s=<optimized out>) at kernel/qguieventdispatcher_glib.cpp:85
#17 0x00007f784d6e0264 in g_main_context_check () from /usr/lib64/libglib-2.0.so.0
#18 0x00007f784d6e0ab2 in ?? () from /usr/lib64/libglib-2.0.so.0
#19 0x00007f784d6e0f59 in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#20 0x00007f78539e18ef in QEventDispatcherGlib::processEvents (this=0x60d320, flags=<optimized out>) at kernel/qeventdispatcher_glib.cpp:424
#21 0x00007f78544692de in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=<optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#22 0x00007f78539b1682 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#23 0x00007f78539b18d7 in QEventLoop::exec (this=0x7fffe317de70, flags=...) at kernel/qeventloop.cpp:204
#24 0x00007f78539b6435 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1148
#25 0x0000000000403919 in ?? ()
#26 0x00007f78531ba23d in __libc_start_main () from /lib64/libc.so.6
#27 0x0000000000403e51 in _start ()

Reported using DrKonqi