Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.2 (KDE 4.3.2)
Qt Version: 4.5.3
Operating System: Linux 2.6.31.6-desktop-1mnb i686
Distribution: "Mandriva Linux 2010.0"

What I was doing when the application crashed:
I was trying to configure different activities for Desktop, but the Desktop just got to be really strange, the background colors is like falling apart, and the new widgets I added do not show in my panel although do take the space. And the widegets already on my desktop became no more available to either move or configure. Then I decided to turn the different activites off - that's where I got a crash and bug reporter.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0xb56d86d0 (LWP 2275))]

Thread 2 (Thread 0xa7653b70 (LWP 2361)):
#0  0xffffe424 in __kernel_vsyscall ()
#1  0xb75599e5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/i686/libpthread.so.0
#2  0xb75b4fb0 in QWaitCondition::wait () from /usr/lib/libQtCore.so.4
#3  0xb5d01194 in ?? () from /usr/lib/libQtNetwork.so.4
#4  0xb75b3e83 in ?? () from /usr/lib/libQtCore.so.4
#5  0xb7555885 in start_thread () from /lib/i686/libpthread.so.0
#6  0xb5fa657e in clone () from /lib/i686/libc.so.6

Thread 1 (Thread 0xb56d86d0 (LWP 2275)):
[KCrash Handler]
#6  0xb684da97 in QGraphicsItem::isWidget () from /usr/lib/libQtGui.so.4
#7  0xb6850992 in QGraphicsItem::isWindow () from /usr/lib/libQtGui.so.4
#8  0xb68882df in QGraphicsScene::event () from /usr/lib/libQtGui.so.4
#9  0xb623068c in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#10 0xb62380ce in QApplication::notify () from /usr/lib/libQtGui.so.4
#11 0xb6c919e1 in KApplication::notify () from /usr/lib/libkdeui.so.5
#12 0xb76aac0e in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#13 0xb6899e98 in QGraphicsView::viewportEvent () from /usr/lib/libQtGui.so.4
#14 0xb66e67c6 in ?? () from /usr/lib/libQtGui.so.4
#15 0xb76a9dee in QCoreApplicationPrivate::sendThroughObjectEventFilters () from /usr/lib/libQtCore.so.4
#16 0xb6230660 in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#17 0xb623801e in QApplication::notify () from /usr/lib/libQtGui.so.4
#18 0xb6c919e1 in KApplication::notify () from /usr/lib/libkdeui.so.5
#19 0xb76aac0e in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#20 0xb6287abf in QWidget::event () from /usr/lib/libQtGui.so.4
#21 0xb6643c95 in QFrame::event () from /usr/lib/libQtGui.so.4
#22 0xb66e4c3a in QAbstractScrollArea::event () from /usr/lib/libQtGui.so.4
#23 0xb6899c88 in QGraphicsView::event () from /usr/lib/libQtGui.so.4
#24 0xb623068c in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#25 0xb623801e in QApplication::notify () from /usr/lib/libQtGui.so.4
#26 0xb6c919e1 in KApplication::notify () from /usr/lib/libkdeui.so.5
#27 0xb76aac0e in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#28 0xb623b7f4 in QApplication::setActiveWindow () from /usr/lib/libQtGui.so.4
#29 0xb62a743b in QApplication::x11ProcessEvent () from /usr/lib/libQtGui.so.4
#30 0xb62d2d88 in ?? () from /usr/lib/libQtGui.so.4
#31 0xb5e1fb92 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#32 0xb5e23468 in ?? () from /usr/lib/libglib-2.0.so.0
#33 0xb5e2358e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#34 0xb76d68f1 in QEventDispatcherGlib::processEvents () from /usr/lib/libQtCore.so.4
#35 0xb62d24ba in ?? () from /usr/lib/libQtGui.so.4
#36 0xb76a926d in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#37 0xb76a96b9 in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#38 0xb76abb50 in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#39 0xb6230504 in QApplication::exec () from /usr/lib/libQtGui.so.4
#40 0xb2f44bd9 in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#41 0x0804da54 in _start ()

Reported using DrKonqi