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 2.6.31-16-generic i686
Distribution: Ubuntu 9.10

What I was doing when the application crashed:
sometimes desktop crashes when i try to remove a panel containing widgets.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0xb7891700 (LWP 1571))]

Thread 2 (Thread 0xab85ab70 (LWP 1574)):
#0  0x00b6e422 in __kernel_vsyscall ()
#1  0x004b5e15 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0x03b6078d in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0x005cfe67 in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQtCore.so.4
#4  0x027a0922 in ?? () from /usr/lib/libQtNetwork.so.4
#5  0x005cee32 in ?? () from /usr/lib/libQtCore.so.4
#6  0x004b180e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0x03b537ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb7891700 (LWP 1571)):
[KCrash Handler]
#6  0x0162518a in QGraphicsItem::isWidget() const () from /usr/lib/libQtGui.so.4
#7  0x0165e527 in QGraphicsScene::event(QEvent*) () from /usr/lib/libQtGui.so.4
#8  0x01021f54 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#9  0x0102967c in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#10 0x00d41bfa in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#11 0x006bf6cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#12 0x0166f5e7 in QGraphicsView::viewportEvent(QEvent*) () from /usr/lib/libQtGui.so.4
#13 0x014c7a95 in ?? () from /usr/lib/libQtGui.so.4
#14 0x006be83a in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#15 0x01021f2c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#16 0x010295ca in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#17 0x00d41bfa in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#18 0x006bf6cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#19 0x01076ad5 in QWidget::event(QEvent*) () from /usr/lib/libQtGui.so.4
#20 0x01426633 in QFrame::event(QEvent*) () from /usr/lib/libQtGui.so.4
#21 0x014c5faa in QAbstractScrollArea::event(QEvent*) () from /usr/lib/libQtGui.so.4
#22 0x0166f406 in QGraphicsView::event(QEvent*) () from /usr/lib/libQtGui.so.4
#23 0x01021f54 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#24 0x010295ca in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#25 0x00d41bfa in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#26 0x006bf6cb in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#27 0x0102cdf6 in QApplication::setActiveWindow(QWidget*) () from /usr/lib/libQtGui.so.4
#28 0x0109621f in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/libQtGui.so.4
#29 0x010c3502 in ?? () from /usr/lib/libQtGui.so.4
#30 0x05ec5e88 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#31 0x05ec9730 in ?? () from /lib/libglib-2.0.so.0
#32 0x05ec9863 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#33 0x006ea02c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#34 0x010c2be5 in ?? () from /usr/lib/libQtGui.so.4
#35 0x006bdc79 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#36 0x006be0ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#37 0x006c053f in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#38 0x01021dd7 in QApplication::exec() () from /usr/lib/libQtGui.so.4
#39 0x0234180d in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#40 0x0804dde1 in _start ()

Reported using DrKonqi