Application that crashed: kmail
Version of the application: 1.12.1
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.2
Operating System: Linux 2.6.30.8-64.fc11.i686.PAE i686
Distribution: "Fedora release 11 (Leonidas)"

What I was doing when the application crashed:
After a reboot of the local server where dnsmasq was not started due to configuration problems, kmail simply crashed after displaying the message that it was unable to resolve the host name of the mail server.

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#6  0x07dd75dd in KIO::Slave::deref() () from /usr/lib/libkio.so.5
#7  0x07dd8186 in KIO::Slave::gotInput() () from /usr/lib/libkio.so.5
#8  0x07dda573 in KIO::Slave::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libkio.so.5
#9  0x035d3853 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQtCore.so.4
#10 0x035d44b2 in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/libQtCore.so.4
#11 0x07ce0ab7 in KIO::Connection::readyRead() () from /usr/lib/libkio.so.5
#12 0x07ce288e in ?? () from /usr/lib/libkio.so.5
#13 0x07ce29b6 in KIO::Connection::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libkio.so.5
#14 0x035cc47b in QMetaCallEvent::placeMetaCall(QObject*) () from /usr/lib/libQtCore.so.4
#15 0x035cdbc6 in QObject::event(QEvent*) () from /usr/lib/libQtCore.so.4
#16 0x0250a974 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#17 0x025120e9 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#18 0x02f5860a in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#19 0x035bdb0b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#20 0x035be732 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/libQtCore.so.4
#21 0x035be8ed in QCoreApplication::sendPostedEvents(QObject*, int) () from /usr/lib/libQtCore.so.4
#22 0x035e89bf in ?? () from /usr/lib/libQtCore.so.4
#23 0x01174308 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#24 0x011779e0 in ?? () from /lib/libglib-2.0.so.0
#25 0x01177b13 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#26 0x035e85ec in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#27 0x025a9cb5 in ?? () from /usr/lib/libQtGui.so.4
#28 0x035bc0d9 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#29 0x035bc52a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#30 0x035be9af in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#31 0x0250a7f7 in QApplication::exec() () from /usr/lib/libQtGui.so.4
#32 0x0804a592 in _start ()

Reported using DrKonqi