Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.2.90 (KDE 4.2.90 (KDE 4.3 Beta2))
Qt Version: 4.5.0
Operating System: Linux 2.6.28-13-generic x86_64
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
Clicking on a taskmanager desktop icon after switching desktops can lead to this crash

 -- Backtrace:
Application: Plasma Workspace (kdeinit), signal: Segmentation fault
[Current thread is 0 (LWP 4477)]

Thread 2 (Thread 0x7fe29393d950 (LWP 4660)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00007fe2b322c939 in QWaitCondition::wait (this=0x2ca9380, mutex=0x2ca9378, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:87
#2  0x00007fe2b20a94cc in QHostInfoAgent::run (this=0x2ca9360) at kernel/qhostinfo.cpp:260
#3  0x00007fe2b322b952 in QThreadPrivate::start (arg=0x2ca9360) at thread/qthread_unix.cpp:189
#4  0x00007fe2af0ad3ba in start_thread (arg=<value optimized out>) at pthread_create.c:297
#5  0x00007fe2afc91fcd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7fe2b37f6750 (LWP 4477)):
[KCrash Handler]
#5  0x00007fe29887484c in TaskManager::AbstractGroupingStrategy::closeGroup (this=0x30b8cd0, group=0x3122340)
    at /build/buildd/kdebase-workspace-4.2.90/libs/taskmanager/abstractgroupingstrategy.cpp:140
#6  0x00007fe29887b908 in TaskManager::ProgramGroupingStrategy::checkGroup (this=0x30b8cd0) at /build/buildd/kdebase-workspace-4.2.90/libs/taskmanager/strategies/programgroupingstrategy.cpp:193
#7  0x00007fe29887c4ed in TaskManager::ProgramGroupingStrategy::qt_metacall (this=0x30b8cd0, _c=QMetaObject::InvokeMetaMethod, _id=0, _a=<value optimized out>)
    at /build/buildd/kdebase-workspace-4.2.90/obj-x86_64-linux-gnu/libs/taskmanager/programgroupingstrategy.moc:68
#8  0x00007fe2b332a1f2 in QMetaObject::activate (sender=0x3122340, from_signal_index=<value optimized out>, to_signal_index=22, argv=0x1) at kernel/qobject.cpp:3069
#9  0x00007fe29888d572 in TaskManager::TaskGroup::itemRemoved (this=0x235f158, _t1=0x30f8b60) at /build/buildd/kdebase-workspace-4.2.90/obj-x86_64-linux-gnu/libs/taskmanager/taskgroup.moc:143
#10 0x00007fe298876fe2 in TaskManager::GroupManagerPrivate::removeTask (this=0x2c24fd0, task={d = 0x7fffbb82a2b0}) at /build/buildd/kdebase-workspace-4.2.90/libs/taskmanager/groupmanager.cpp:296
#11 0x00007fe298877abe in TaskManager::GroupManagerPrivate::reloadTasks (this=0x2c24fd0) at /build/buildd/kdebase-workspace-4.2.90/libs/taskmanager/groupmanager.cpp:151
#12 0x00007fe2988790b0 in TaskManager::GroupManager::qt_metacall (this=0x29e16e0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fffbb82a490)
    at /build/buildd/kdebase-workspace-4.2.90/obj-x86_64-linux-gnu/libs/taskmanager/groupmanager.moc:95
#13 0x00007fe2b332a1f2 in QMetaObject::activate (sender=0x2c25100, from_signal_index=<value optimized out>, to_signal_index=8, argv=0x1) at kernel/qobject.cpp:3069
#14 0x00007fe298890741 in TaskManager::TaskManager::desktopChanged (this=0x235f158, _t1=1) at /build/buildd/kdebase-workspace-4.2.90/obj-x86_64-linux-gnu/libs/taskmanager/taskmanager.moc:180
#15 0x00007fe298893b9e in TaskManager::TaskManager::qt_metacall (this=0x2c25100, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fffbb82a640)
    at /build/buildd/kdebase-workspace-4.2.90/obj-x86_64-linux-gnu/libs/taskmanager/taskmanager.moc:111
#16 0x00007fe2b332a1f2 in QMetaObject::activate (sender=0x26aa320, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x1) at kernel/qobject.cpp:3069
#17 0x00007fe2b1b0e4de in KWindowSystem::currentDesktopChanged (this=0x235f158, _t1=1) at /build/buildd/kde4libs-4.2.90/obj-x86_64-linux-gnu/kdeui/kwindowsystem.moc:113
#18 0x00007fe2b1b10e33 in KWindowSystemPrivate::x11Event (this=0x26aa5b0, ev=0x7fffbb82b060) at /build/buildd/kde4libs-4.2.90/kdeui/windowmanagement/kwindowsystem_x11.cpp:139
#19 0x00007fe2b19e0483 in KApplication::x11EventFilter (this=<value optimized out>, _event=0x7fffbb82b060) at /build/buildd/kde4libs-4.2.90/kdeui/kernel/kapplication.cpp:911
#20 0x00007fe2a85ce817 in PlasmaApp::x11EventFilter (this=0x23b4300, event=0x7fffbb82b060) at /build/buildd/kdebase-workspace-4.2.90/plasma/shells/desktop/plasmaapp.cpp:444
#21 0x00007fe2b08fab1f in qt_x11EventFilter (ev=0x7fffbb82b060) at kernel/qapplication_x11.cpp:375
#22 0x00007fe2b090dfaf in QApplication::x11ProcessEvent (this=0x23b4300, event=0x7fffbb82b060) at kernel/qapplication_x11.cpp:3273
#23 0x00007fe2b0937464 in x11EventSourceDispatch (s=0x23f92a0, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#24 0x00007fe2af2fc20a in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#25 0x00007fe2af2ff8e0 in ?? () from /usr/lib/libglib-2.0.so.0
#26 0x00007fe2af2ffa7c in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#27 0x00007fe2b333de6f in QEventDispatcherGlib::processEvents (this=0x23f4850, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:323
#28 0x00007fe2b0936bef in QGuiEventDispatcherGlib::processEvents (this=0x235f158, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#29 0x00007fe2b3313002 in QEventLoop::processEvents (this=<value optimized out>, flags={i = -1149062320}) at kernel/qeventloop.cpp:149
#30 0x00007fe2b33133cd in QEventLoop::exec (this=0x7fffbb82b390, flags={i = -1149062240}) at kernel/qeventloop.cpp:200
#31 0x00007fe2b3315694 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#32 0x00007fe2a85bb7eb in kdemain (argc=1, argv=0x23aad70) at /build/buildd/kdebase-workspace-4.2.90/plasma/shells/desktop/main.cpp:50
#33 0x000000000040714e in launch (argc=1, _name=0x23c1308 "/usr/bin/plasma-desktop", args=<value optimized out>, cwd=0x0, envc=0, envs=0x23c1328 "", reset_env=false, tty=0x0, avoid_loops=false, 
    startup_id_str=0x40a308 "0") at /build/buildd/kde4libs-4.2.90/kinit/kinit.cpp:671
#34 0x0000000000407978 in handle_launcher_request (sock=7, who=<value optimized out>) at /build/buildd/kde4libs-4.2.90/kinit/kinit.cpp:1163
#35 0x0000000000407f25 in handle_requests (waitForPid=0) at /build/buildd/kde4libs-4.2.90/kinit/kinit.cpp:1356
#36 0x0000000000408a66 in main (argc=2, argv=0x7fffbb82c228, envp=0x7fffbb82c240) at /build/buildd/kde4libs-4.2.90/kinit/kinit.cpp:1783

Reported using DrKonqi