Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.2 (KDE 4.3.2)
Qt Version: 4.5.2
Operating System: Linux 2.6.31-14-generic i686
Distribution: Ubuntu 9.10

What I was doing when the application crashed:
On Kubuntu 9.10 task bar crashes randomly.  To get the task bar I need to delete $HOME/.kde directory.  Restarting KDE or X.org doesn't help.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0xb77f6700 (LWP 13179))]

Thread 2 (Thread 0xaa880b70 (LWP 13184)):
#0  0x00372422 in __kernel_vsyscall ()
#1  0x009c7e15 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0x0092d78d in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0x00bade67 in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQtCore.so.4
#4  0x028d1922 in ?? () from /usr/lib/libQtNetwork.so.4
#5  0x00bace32 in ?? () from /usr/lib/libQtCore.so.4
#6  0x009c380e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0x009207ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb77f6700 (LWP 13179)):
[KCrash Handler]
#6  0x051f818a in QGraphicsItem::isWidget() const () from /usr/lib/libQtGui.so.4
#7  0x05231527 in QGraphicsScene::event(QEvent*) () from /usr/lib/libQtGui.so.4
#8  0x04bf4f54 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#9  0x04bfc67c in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#10 0x00f63bfa in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#11 0x00c9d6cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#12 0x052425e7 in QGraphicsView::viewportEvent(QEvent*) () from /usr/lib/libQtGui.so.4
#13 0x0509aa95 in ?? () from /usr/lib/libQtGui.so.4
#14 0x00c9c83a in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#15 0x04bf4f2c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#16 0x04bfc5ca in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#17 0x00f63bfa in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#18 0x00c9d6cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#19 0x04c49ad5 in QWidget::event(QEvent*) () from /usr/lib/libQtGui.so.4
#20 0x04ff9633 in QFrame::event(QEvent*) () from /usr/lib/libQtGui.so.4
#21 0x05098faa in QAbstractScrollArea::event(QEvent*) () from /usr/lib/libQtGui.so.4
#22 0x05242406 in QGraphicsView::event(QEvent*) () from /usr/lib/libQtGui.so.4
#23 0x04bf4f54 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#24 0x04bfc5ca in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#25 0x00f63bfa in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#26 0x00c9d6cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#27 0x04bffdf6 in QApplication::setActiveWindow(QWidget*) () from /usr/lib/libQtGui.so.4
#28 0x04c6921f in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/libQtGui.so.4
#29 0x04c96502 in ?? () from /usr/lib/libQtGui.so.4
#30 0x00a84e78 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#31 0x00a88720 in ?? () from /lib/libglib-2.0.so.0
#32 0x00a88853 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#33 0x00cc802c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#34 0x04c95be5 in ?? () from /usr/lib/libQtGui.so.4
#35 0x00c9bc79 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#36 0x00c9c0ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#37 0x00c9e53f in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#38 0x04bf4dd7 in QApplication::exec() () from /usr/lib/libQtGui.so.4
#39 0x017ec80d in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#40 0x0804dde1 in _start ()

Reported using DrKonqi