Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.2.85 (KDE 4.2.85 (KDE 4.3 Beta1))
Qt Version: 4.5.0
Operating System: Linux 2.6.28-11-generic i686
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
1) Load an application that takes a few seconds to load (I'm using Kick Off as my launcher).
2) Move the mouse over the application's entry in the task bar that appears whilst it is loading
3) Crash.

I've tested it with a few apps (KDevelop is a useful one), and it's very repeatable.

 -- Backtrace:
Application: Plasma Workspace (plasma-desktop), signal: Segmentation fault
[Current thread is 0 (LWP 18283)]

Thread 2 (Thread 0xa89fbb90 (LWP 18293)):
#0  0xb7f20430 in __kernel_vsyscall ()
#1  0xb63480e5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0xb63ca9b2 in QWaitCondition::wait (this=0x9996b08, mutex=0x9996b04, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#3  0xb7875152 in QHostInfoAgent::run (this=0x9996af8) at kernel/qhostinfo.cpp:260
#4  0xb63c996e in QThreadPrivate::start (arg=0x9996af8) at thread/qthread_unix.cpp:189
#5  0xb63444ff in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#6  0xb619b49e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb4aefa40 (LWP 18283)):
[KCrash Handler]
#6  TaskManager::Task::window (this=0xa54a8f8) at /media/disk/kde4/src/kdebase/workspace/libs/taskmanager/task.cpp:355
#7  0xb64ce15f in QObject::event (this=0xa54a8f8, e=0x0) at kernel/qobject.cpp:1082
#8  0xb6def067 in QGraphicsWidget::event (this=0xa54a8f8, event=0xbfe3bb2c) at graphicsview/qgraphicswidget.cpp:1317
#9  0xb676bf2c in QApplicationPrivate::notify_helper (this=0x92f70e0, receiver=0xa54a8f8, e=0xbfe3bb2c) at kernel/qapplication.cpp:4084
#10 0xb677422e in QApplication::notify (this=0x92f0fb0, receiver=0xa54a8f8, e=0xbfe3bb2c) at kernel/qapplication.cpp:3631
#11 0xb75f4f4d in KApplication::notify (this=0x92f0fb0, receiver=0xa54a8f8, event=0xbfe3bb2c) at /media/disk/kde4/src/kdelibs/kdeui/kernel/kapplication.cpp:307
#12 0xb64bda3b in QCoreApplication::notifyInternal (this=0x92f0fb0, receiver=0xa54a8f8, event=0xbfe3bb2c) at kernel/qcoreapplication.cpp:602
#13 0xb64ecd71 in QTimerInfoList::activateTimers (this=0x92fe734) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#14 0xb64e94e0 in timerSourceDispatch (source=0x92fe700) at kernel/qeventdispatcher_glib.cpp:164
#15 0xb4db7b88 in IA__g_main_context_dispatch (context=0x92fdc78) at /build/buildd/glib2.0-2.20.1/glib/gmain.c:1814
#16 0xb4dbb0eb in g_main_context_iterate (context=0x92fdc78, block=1, dispatch=1, self=0x92f62d8) at /build/buildd/glib2.0-2.20.1/glib/gmain.c:2448
#17 0xb4dbb268 in IA__g_main_context_iteration (context=0x92fdc78, may_block=1) at /build/buildd/glib2.0-2.20.1/glib/gmain.c:2511
#18 0xb64e9438 in QEventDispatcherGlib::processEvents (this=0x92f66c8, flags={i = -1075594072}) at kernel/qeventdispatcher_glib.cpp:323
#19 0xb680d3f5 in QGuiEventDispatcherGlib::processEvents (this=0x92f66c8, flags={i = -1075594024}) at kernel/qguieventdispatcher_glib.cpp:202
#20 0xb64bc06a in QEventLoop::processEvents (this=0xbfe3bd50, flags={i = -1075593960}) at kernel/qeventloop.cpp:149
#21 0xb64bc4aa in QEventLoop::exec (this=0xbfe3bd50, flags={i = -1075593896}) at kernel/qeventloop.cpp:200
#22 0xb64be959 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#23 0xb676bda7 in QApplication::exec () at kernel/qapplication.cpp:3553
#24 0xb7edb090 in kdemain (argc=1, argv=0xbfe3bf04) at /media/disk/kde4/src/kdebase/workspace/plasma/shells/desktop/main.cpp:50
#25 0x08048772 in main (argc=-1074790400, argv=0x0) at /media/disk/kde4/build/kdebase/workspace/plasma/shells/desktop/plasma-desktop_dummy.cpp:3