Version:           svn (using Devel)
Compiler:          gcc 4.3.2 
OS:                Linux
Installed from:    Compiled sources

x86_64 athlon64 x2

I think that what interests you is below (at thread 1). This happened when I started Kopete. I bet it's related to some offline messages sent to me (I then started Kopete again and it worked... maybe a race condition or thread issue?):

Application: Kopete (kopete), signal SIGSEGV
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 140420007966544 (LWP 9676)]
[New Thread 1116846416 (LWP 9702)]
[New Thread 1133631824 (LWP 9698)]
[New Thread 1108453712 (LWP 9688)]
[New Thread 1092561232 (LWP 9686)]
0x00007fb60d36e1a1 in ?? () from /lib64/libc.so.6
[Current thread is 0 (LWP 9676)]

Thread 5 (Thread 1092561232 (LWP 9686)):
#0  0x00007fb60eba3676 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007fb6123e9589 in QWaitCondition::wait (this=0x1d3bc90, mutex=0x1d3bc88, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:88
#2  0x00007fb60fd5dc9c in QHostInfoAgent::run (this=0x1d3bc70) at kernel/qhostinfo.cpp:247
#3  0x00007fb6123e85c2 in QThreadPrivate::start (arg=0x1d3bc70) at thread/qthread_unix.cpp:191
#4  0x00007fb60eb9ef9b in start_thread () from /lib64/libpthread.so.0
#5  0x00007fb60d39aaad in clone () from /lib64/libc.so.6

Thread 4 (Thread 1108453712 (LWP 9688)):
#0  0xffffffffff600177 in ?? ()
#1  0x00007fff1cbff5eb in ?? ()
#2  0x00007fb60b7392cf in clock_gettime () from /lib64/librt.so.1
#3  0x00007fb6124f786d in QTimerInfoList::getTime (this=<value optimized out>, t=@0x1226f30) at kernel/qeventdispatcher_unix.cpp:341
#4  0x00007fb6124f7a61 in QTimerInfoList::updateCurrentTime (this=0x42119cc0) at kernel/qeventdispatcher_unix.cpp:299
#5  0x00007fb6124f9623 in QTimerInfoList::timerWait (this=0x42119cc0, tm=@0x42119cc0) at kernel/qeventdispatcher_unix.cpp:422
#6  0x00007fb6124f5fa4 in timerSourcePrepare (source=<value optimized out>, timeout=0x42119db4) at kernel/qeventdispatcher_glib.cpp:142
#7  0x00007fb60b48fe8a in g_main_context_prepare () from /usr/local/lib/libglib-2.0.so.0
#8  0x00007fb60b49029a in g_main_context_iterate () from /usr/local/lib/libglib-2.0.so.0
#9  0x00007fb60b49075b in g_main_context_iteration () from /usr/local/lib/libglib-2.0.so.0
#10 0x00007fb6124f5e06 in QEventDispatcherGlib::processEvents (this=0x1792f60, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:327
#11 0x00007fb6124cccc2 in QEventLoop::processEvents (this=<value optimized out>, flags={i = 1108451072}) at kernel/qeventloop.cpp:149
#12 0x00007fb6124cce4d in QEventLoop::exec (this=0x1df1d80, flags={i = 1108451472}) at kernel/qeventloop.cpp:200
#13 0x00007fb601955e8b in QCA::SyncThread::run () from /usr/local/kde4/lib/libqca.so.2
#14 0x00007fb6123e85c2 in QThreadPrivate::start (arg=0x1226a10) at thread/qthread_unix.cpp:191
#15 0x00007fb60eb9ef9b in start_thread () from /lib64/libpthread.so.0
#16 0x00007fb60d39aaad in clone () from /lib64/libc.so.6

Thread 3 (Thread 1133631824 (LWP 9698)):
#0  0x00007fb60eba38ea in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007fb6123e9567 in QWaitCondition::wait (this=0x1a80758, mutex=0x1a80750, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  0x00007fb6123df9e9 in QThreadPoolThread::run (this=0xf7be20) at concurrent/qthreadpool.cpp:141
#3  0x00007fb6123e85c2 in QThreadPrivate::start (arg=0xf7be20) at thread/qthread_unix.cpp:191
#4  0x00007fb60eb9ef9b in start_thread () from /lib64/libpthread.so.0
#5  0x00007fb60d39aaad in clone () from /lib64/libc.so.6

Thread 2 (Thread 1116846416 (LWP 9702)):
#0  0x00007fb60d394b62 in ?? () from /lib64/libc.so.6
#1  0x00007fb601361e3a in posix_timer_do () from /usr/local/lib/libortp.so.5
#2  0x00007fb601362add in rtp_scheduler_schedule () from /usr/local/lib/libortp.so.5
#3  0x00007fb60eb9ef9b in start_thread () from /lib64/libpthread.so.0
#4  0x00007fb60d39aaad in clone () from /lib64/libc.so.6

Thread 1 (Thread 140420007966544 (LWP 9676)):
[KCrash Handler]
#5  0x00007fb60db4cda1 in std::string::compare () from /usr/local/lib64/libstdc++.so.6
#6  0x00007fb60229d517 in MSN::NotificationServerConnection::gotMailData () from /usr/local/lib/libmsn.so.0.1
#7  0x00007fb60229de08 in MSN::NotificationServerConnection::message_initialmdatanotification () from /usr/local/lib/libmsn.so.0.1
#8  0x00007fb602298338 in MSN::NotificationServerConnection::handle_MSG () from /usr/local/lib/libmsn.so.0.1
#9  0x00007fb60229c317 in MSN::NotificationServerConnection::handleIncomingData () from /usr/local/lib/libmsn.so.0.1
#10 0x00007fb602284fe0 in MSN::Connection::dataArrivedOnSocket () from /usr/local/lib/libmsn.so.0.1
#11 0x00007fb6025349dd in WlmSocket::qt_metacall (this=0x135c6a0, _c=QMetaObject::InvokeMetaMethod, _id=1, _a=<value optimized out>)
    at /usr/local/src/svn/kdenetwork/b/kopete/protocols/wlm/wlmsocket.moc:69
#12 0x00007fb6124e230c in QMetaObject::activate (sender=0x135c6a0, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x1) at kernel/qobject.cpp:3028
#13 0x00007fb60fd8ee62 in QSslSocket::qt_metacall (this=0x135c6a0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff1cb5e000) at .moc/release-shared/moc_qsslsocket.cpp:113
#14 0x00007fb6025349ad in WlmSocket::qt_metacall (this=0x7fb6022edda6, _c=36625830, _id=43562096, _a=0x1) at /usr/local/src/svn/kdenetwork/b/kopete/protocols/wlm/wlmsocket.moc:64
#15 0x00007fb6124e230c in QMetaObject::activate (sender=0x1397010, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x1) at kernel/qobject.cpp:3028
#16 0x00007fb60fd75f57 in QAbstractSocketPrivate::canReadNotification (this=0x1b80350) at socket/qabstractsocket.cpp:574
#17 0x00007fb60fd67261 in QReadNotifier::event (this=<value optimized out>, e=0x7fb6022edda6) at socket/qnativesocketengine.cpp:974
#18 0x00007fb60df65acd in QApplicationPrivate::notify_helper (this=0xcb47b0, receiver=0x257b2f0, e=0x7fff1cb5e4c0) at kernel/qapplication.cpp:3809
#19 0x00007fb60df6d6aa in QApplication::notify (this=0x7fff1cb5e7b0, receiver=0x257b2f0, e=0x7fff1cb5e4c0) at kernel/qapplication.cpp:3774
#20 0x00007fb60f6add6b in KApplication::notify (this=0x7fff1cb5e7b0, receiver=0x257b2f0, event=0x7fff1cb5e4c0) at /usr/local/src/svn/kdelibs/kdeui/kernel/kapplication.cpp:307
#21 0x00007fb6124ce35e in QCoreApplication::notifyInternal (this=0x7fff1cb5e7b0, receiver=0x257b2f0, event=0x7fff1cb5e4c0) at kernel/qcoreapplication.cpp:593
#22 0x00007fb6124f6059 in socketNotifierSourceDispatch (source=0xcb71a0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#23 0x00007fb60b48ced1 in g_main_context_dispatch () from /usr/local/lib/libglib-2.0.so.0
#24 0x00007fb60b49059d in g_main_context_iterate () from /usr/local/lib/libglib-2.0.so.0
#25 0x00007fb60b49075b in g_main_context_iteration () from /usr/local/lib/libglib-2.0.so.0
#26 0x00007fb6124f5def in QEventDispatcherGlib::processEvents (this=0xcb0bd0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:325
#27 0x00007fb60dff48ff in QGuiEventDispatcherGlib::processEvents (this=0x7fb6022edda6, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#28 0x00007fb6124cccc2 in QEventLoop::processEvents (this=<value optimized out>, flags={i = 481683168}) at kernel/qeventloop.cpp:149
#29 0x00007fb6124cce4d in QEventLoop::exec (this=0x7fff1cb5e720, flags={i = 481683248}) at kernel/qeventloop.cpp:200
#30 0x00007fb6124cf28d in QCoreApplication::exec () at kernel/qcoreapplication.cpp:851
#31 0x00000000004491fc in main (argc=1, argv=0x7fff1cb5f578) at /usr/local/src/svn/kdenetwork/kopete/kopete/main.cpp:102