Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.3 (KDE 4.3.3)
Qt Version: 4.6.0
Operating System: Linux 2.6.30.9-96.fc11.x86_64 x86_64

What I was doing when the application crashed:
Happens from time to time KDE 4.3.3 with QT4.6. After switching between workspaces the task bar gets corrupted (entries go onto two rows, but text not scaled to fit and a gap at the beginning), and sometimes immediately, sometimes a minute or so later plasma will crash.

Sometimes prior to the crash a widget's modification handle will get stuck visible (ie doesn't hide when you move the cursor off the widget).

 -- Backtrace:
Application: Plasma Workspace (plasma-desktop), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f8a2ea06860 (LWP 2569))]

Thread 3 (Thread 0x7f8a1840d910 (LWP 2571)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00000032aa4745eb in QWaitConditionPrivate::wait (time=<value optimized out>, this=<value optimized out>) at thread/qwaitcondition_unix.cpp:87
#2  QWaitCondition::wait (time=<value optimized out>, this=<value optimized out>) at thread/qwaitcondition_unix.cpp:159
#3  0x00000032ab287404 in QHostInfoAgent::run (this=0x24e76b0) at kernel/qhostinfo.cpp:252
#4  0x00000032aa473635 in QThreadPrivate::start (arg=0x24e76b0) at thread/qthread_unix.cpp:244
#5  0x0000003c5c20686a in start_thread (arg=<value optimized out>) at pthread_create.c:297
#6  0x0000003c5b2de3bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f8a0bbe6910 (LWP 5061)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00000032b2737676 in WTF::TCMalloc_PageHeap::scavengerThread (this=0x32b2a15ba0) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2304
#2  0x00000032b27376b9 in WTF::TCMalloc_PageHeap::runScavengerThread (context=0x32b2a23c6c) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1438
#3  0x0000003c5c20686a in start_thread (arg=<value optimized out>) at pthread_create.c:297
#4  0x0000003c5b2de3bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f8a2ea06860 (LWP 2569)):
[KCrash Handler]
#5  0x00000032ac3a3624 in QGraphicsLayoutItem::parentLayoutItem (this=0x3341af0) at graphicsview/qgraphicslayoutitem.cpp:782
#6  0x00000032ac3a28ca in QGraphicsLayoutPrivate::addChildLayoutItem (this=0x27d5ae0, layoutItem=0x3341af0) at graphicsview/qgraphicslayout_p.cpp:150
#7  0x00000032ac377e73 in QGraphicsGridLayout::addItem (this=0x27ce840, item=0x3341af0, row=<value optimized out>, column=<value optimized out>, rowSpan=<value optimized out>, 
    columnSpan=<value optimized out>, alignment={i = 0}) at graphicsview/qgraphicsgridlayout.cpp:162
#8  0x00007f8a194f4796 in TaskItemLayout::layoutItems (this=0x27ce830) at /usr/src/debug/kdebase-workspace-4.3.3/plasma/applets/tasks/taskitemlayout.cpp:375
#9  0x00007f8a194f4cdb in TaskItemLayout::insert (this=0x27ce830, index=<value optimized out>, item=0x332fa90) at /usr/src/debug/kdebase-workspace-4.3.3/plasma/applets/tasks/taskitemlayout.cpp:129
#10 0x00007f8a194f4ed0 in TaskItemLayout::addTaskItem (this=0x27ce830, item=0x332fa90) at /usr/src/debug/kdebase-workspace-4.3.3/plasma/applets/tasks/taskitemlayout.cpp:82
#11 0x00007f8a19501068 in TaskGroupItem::itemAdded (this=0x27cf790, groupableItem=0x2e57bd0) at /usr/src/debug/kdebase-workspace-4.3.3/plasma/applets/tasks/taskgroupitem.cpp:477
#12 0x00007f8a195016e4 in TaskGroupItem::qt_metacall (this=0x27cf790, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fffa2596e00)
    at /usr/src/debug/kdebase-workspace-4.3.3/x86_64-redhat-linux-gnu/plasma/applets/tasks/taskgroupitem.moc:113
#13 0x00000032aa5784d3 in QMetaObject::activate (sender=0x27d7d60, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x1) at kernel/qobject.cpp:3294
#14 0x00000032afc30bff in TaskManager::TaskGroup::itemAdded (this=0x3341af0, _t1=0x2e57bd0) at /usr/src/debug/kdebase-workspace-4.3.3/x86_64-redhat-linux-gnu/libs/taskmanager/taskgroup.moc:145
#15 0x00000032afc314df in TaskManager::TaskGroup::add (this=0x27d7d60, item=0x2e57bd0) at /usr/src/debug/kdebase-workspace-4.3.3/libs/taskmanager/taskgroup.cpp:138
#16 0x00000032afc1ae64 in TaskManager::GroupManagerPrivate::addTask (this=0x24279d0, task={d = 0x25792e0}) at /usr/src/debug/kdebase-workspace-4.3.3/libs/taskmanager/groupmanager.cpp:290
#17 0x00000032afc1b74b in TaskManager::GroupManagerPrivate::actuallyReloadTasks (this=0x24279d0) at /usr/src/debug/kdebase-workspace-4.3.3/libs/taskmanager/groupmanager.cpp:155
#18 0x00000032afc1cf79 in TaskManager::GroupManager::qt_metacall (this=0x27cda00, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fffa2597080)
    at /usr/src/debug/kdebase-workspace-4.3.3/x86_64-redhat-linux-gnu/libs/taskmanager/groupmanager.moc:108
#19 0x00000032aa5784d3 in QMetaObject::activate (sender=0x2427a38, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x1) at kernel/qobject.cpp:3294
#20 0x00000032aa57514e in QObject::event (this=0x2427a38, e=0x7fffa2597740) at kernel/qobject.cpp:1224
#21 0x00000032abdab90c in QApplicationPrivate::notify_helper (this=0x1da6200, receiver=0x2427a38, e=0x7fffa2597740) at kernel/qapplication.cpp:4242
#22 0x00000032abdb1e85 in QApplication::notify (this=0x1d8d5d0, receiver=0x2427a38, e=0x7fffa2597740) at kernel/qapplication.cpp:4125
#23 0x00000032ad411be6 in KApplication::notify (this=0x1d8d5d0, receiver=0x2427a38, event=0x7fffa2597740) at /usr/src/debug/kdelibs-4.3.3/kdeui/kernel/kapplication.cpp:302
#24 0x00000032aa5656ac in QCoreApplication::notifyInternal (this=0x1d8d5d0, receiver=0x2427a38, event=0x7fffa2597740) at kernel/qcoreapplication.cpp:704
#25 0x00000032aa5921a2 in QCoreApplication::sendEvent (event=<value optimized out>, receiver=<value optimized out>) at kernel/qcoreapplication.h:215
#26 QTimerInfoList::activateTimers (event=<value optimized out>, receiver=<value optimized out>) at kernel/qeventdispatcher_unix.cpp:603
#27 0x00000032aa58edc8 in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#28 idleTimerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:231
#29 0x000000358643790e in g_main_dispatch (context=<value optimized out>) at gmain.c:1824
#30 IA__g_main_context_dispatch (context=<value optimized out>) at gmain.c:2377
#31 0x000000358643b0e8 in g_main_context_iterate (context=0x1da8920, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>) at gmain.c:2455
#32 0x000000358643b20a in IA__g_main_context_iteration (context=0x1da8920, may_block=1) at gmain.c:2518
#33 0x00000032aa58ea93 in QEventDispatcherGlib::processEvents (this=0x1d76e40, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:407
#34 0x00000032abe57e2e in QGuiEventDispatcherGlib::processEvents (this=0x3341af0, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#35 0x00000032aa563fe2 in QEventLoop::processEvents (this=<value optimized out>, flags={i = 36}) at kernel/qeventloop.cpp:149
#36 0x00000032aa5643bc in QEventLoop::exec (this=0x7fffa25979e0, flags={i = 0}) at kernel/qeventloop.cpp:201
#37 0x00000032aa5667d9 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#38 0x00000032aa03af4f in kdemain (argc=<value optimized out>, argv=<value optimized out>) at /usr/src/debug/kdebase-workspace-4.3.3/plasma/shells/desktop/main.cpp:50
#39 0x0000003c5b21ea2d in __libc_start_main (main=<value optimized out>, argc=<value optimized out>, ubp_av=<value optimized out>, init=<value optimized out>, fini=<value optimized out>, 
    rtld_fini=<value optimized out>, stack_end=0x7fffa2597ce8) at libc-start.c:220
#40 0x0000000000400779 in _start ()

Reported using DrKonqi