Version:            (using KDE 4.1.3)
OS:                Linux
Installed from:    Ubuntu Packages

Summary says it all, really: I just double-clicked on an event and this happened:

Application: Kontact (kontact), signal SIGSEGV
(no debugging symbols found)
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread 0x7fffa6e796f0 (LWP 424)]
[KCrash handler]
#5  0x000000000a378450 in ?? ()
#6  0x00007fff9ed9f5c0 in KCal::IncidenceFormatter::extensiveDisplayString (
    incidence=0xa2b6410)
    at /build/buildd/kdepimlibs-4.1.3/kcal/incidenceformatter.cpp:513
#7  0x00007fff89569619 in KOEventViewer::appendIncidence ()
   from /usr/lib/libkorganizer_eventviewer.so.4
#8  0x00007fff895695d0 in KOEventViewer::setIncidence ()
   from /usr/lib/libkorganizer_eventviewer.so.4
#9  0x00007fff89d16013 in CalendarView::showIncidence ()
   from /usr/lib/libkorganizerprivate.so.4
#10 0x00007fff89d237b6 in CalendarView::editIncidence ()
   from /usr/lib/libkorganizerprivate.so.4
#11 0x00007fff89d267c5 in CalendarView::qt_metacall ()
   from /usr/lib/libkorganizerprivate.so.4
#12 0x00007fffa69cb134 in QMetaObject::activate ()
   from /usr/lib/libQtCore.so.4
#13 0x00007fff899e5612 in KOrg::BaseView::editIncidenceSignal ()
   from /usr/lib/libkorganizer_interfaces.so.4
#14 0x00007fff89d7b051 in ?? () from /usr/lib/libkorganizerprivate.so.4
#15 0x00007fff89cfc698 in ?? () from /usr/lib/libkorganizerprivate.so.4
#16 0x00007fffa522edd0 in QGraphicsScene::event () from /usr/lib/libQtGui.so.4
#17 0x00007fffa4cecc3d in QApplicationPrivate::notify_helper ()
   from /usr/lib/libQtGui.so.4
#18 0x00007fffa4cf49ba in QApplication::notify () from /usr/lib/libQtGui.so.4
#19 0x00007fffa6032fcb in KApplication::notify (this=0x7fffaeebd540, 
    receiver=0xa0029b0, event=0x7fffaeebbeb0)
    at /build/buildd/kde4libs-4.1.3/kdeui/kernel/kapplication.cpp:311
#20 0x00007fffa69b6d61 in QCoreApplication::notifyInternal ()
   from /usr/lib/libQtCore.so.4
#21 0x00007fffa523a276 in QGraphicsView::mouseDoubleClickEvent ()
   from /usr/lib/libQtGui.so.4
#22 0x00007fffa4d3f17c in QWidget::event () from /usr/lib/libQtGui.so.4
#23 0x00007fffa523c9bb in QGraphicsView::viewportEvent ()
   from /usr/lib/libQtGui.so.4
#24 0x00007fffa69b6038 in QCoreApplicationPrivate::sendThroughObjectEventFilters () from /usr/lib/libQtCore.so.4
#25 0x00007fffa4cecc0c in QApplicationPrivate::notify_helper ()
   from /usr/lib/libQtGui.so.4
#26 0x00007fffa4cf522a in QApplication::notify () from /usr/lib/libQtGui.so.4
#27 0x00007fffa6032fcb in KApplication::notify (this=0x7fffaeebd540, 
    receiver=0xa0035a0, event=0x7fffaeebc700)
    at /build/buildd/kde4libs-4.1.3/kdeui/kernel/kapplication.cpp:311
#28 0x00007fffa69b6d61 in QCoreApplication::notifyInternal ()
   from /usr/lib/libQtCore.so.4
#29 0x00007fffa4cf45c8 in QApplicationPrivate::sendMouseEvent ()
   from /usr/lib/libQtGui.so.4
#30 0x00007fffa4d58be9 in ?? () from /usr/lib/libQtGui.so.4
#31 0x00007fffa4d57607 in QApplication::x11ProcessEvent ()
   from /usr/lib/libQtGui.so.4
#32 0x00007fffa4d7f2c4 in ?? () from /usr/lib/libQtGui.so.4
#33 0x00007fffa3bf1d3b in g_main_context_dispatch ()
   from /usr/lib/libglib-2.0.so.0
#34 0x00007fffa3bf550d in ?? () from /usr/lib/libglib-2.0.so.0
#35 0x00007fffa3bf56cb in g_main_context_iteration ()
   from /usr/lib/libglib-2.0.so.0
#36 0x00007fffa69df15f in QEventDispatcherGlib::processEvents ()
   from /usr/lib/libQtCore.so.4
#37 0x00007fffa4d7ea6f in ?? () from /usr/lib/libQtGui.so.4
#38 0x00007fffa69b5682 in QEventLoop::processEvents ()
   from /usr/lib/libQtCore.so.4
#39 0x00007fffa69b580d in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#40 0x00007fffa69b7cbd in QCoreApplication::exec ()
   from /usr/lib/libQtCore.so.4
#41 0x00000000004048e5 in _start ()
#0  0x00007fffa454b5f0 in __nanosleep_nocancel () from /lib/libc.so.6