Please read the following page and provide a useful backtrace for this crash : http://techbase.kde.org/Development/Tutorials/Debugging/How_to_create_useful_crash_reports

If you can reproduce this with the latest KDE, can you provide a useful backtrace as described at http://techbase.kde.org/Development/Tutorials/Debugging/How_to_create_useful_crash_reports and include the console output?

You should be able to get the console output of plasma by doing something like

grep plasma ~/.xsession-errors > plasma.log

or by doing

kquitapp plasma; plasma

to get plasma to run on a Konsole terminal before trying to reproduce the crash.

Here's one from FreeBSD port (PC-BSD),

Application: Plasma Workspace (plasma), signal SIGABRT
[New Thread 0x82f5600 (LWP 100141)]
[New Thread 0x81aca00 (LWP 100140)]
[New Thread 0x81abb00 (LWP 100139)]
[New Thread 0x8101100 (LWP 100131)]
[Switching to Thread 0x82f5600 (LWP 100141)]
[KCrash handler]
#6  0x2a6e4c0b in thr_kill () from /lib/libc.so.7
#7  0x299b15b6 in pthread_kill () from /lib/libthr.so.3
#8  0x299af163 in raise () from /lib/libthr.so.3
#9  0x2a776e6a in abort () from /lib/libc.so.7
#10 0x2a5f40c0 in __gnu_cxx::__verbose_terminate_handler ()
   from /usr/lib/libstdc++.so.6
#11 0x2a5f856a in std::set_unexpected () from /usr/lib/libstdc++.so.6
#12 0x2a5f85b2 in std::terminate () from /usr/lib/libstdc++.so.6
#13 0x2a6457c5 in __cxa_pure_virtual () from /usr/lib/libstdc++.so.6
#14 0x2a3619c9 in QGraphicsItem::sceneBoundingRect ()
   from /usr/local/lib/qt4/libQtGui.so.4
#15 0x2a37fbd5 in QGraphicsScenePrivate::estimateItemsInRect ()
   from /usr/local/lib/qt4/libQtGui.so.4
#16 0x2a38ee9e in QGraphicsViewPrivate::itemsInArea ()
   from /usr/local/lib/qt4/libQtGui.so.4
#17 0x2a38f6b4 in QGraphicsView::items ()
   from /usr/local/lib/qt4/libQtGui.so.4
#18 0x2a38f7b2 in QGraphicsView::itemAt ()
   from /usr/local/lib/qt4/libQtGui.so.4
#19 0x2a35eb15 in QGraphicsItem::unsetCursor ()
   from /usr/local/lib/qt4/libQtGui.so.4
#20 0x2a3a95e2 in QGraphicsProxyWidgetPrivate::setWidget_helper ()
   from /usr/local/lib/qt4/libQtGui.so.4
#21 0x2a3a9aef in QGraphicsProxyWidget::setWidget ()
   from /usr/local/lib/qt4/libQtGui.so.4
#22 0x2a3a9c96 in QGraphicsProxyWidget::~QGraphicsProxyWidget ()
   from /usr/local/lib/qt4/libQtGui.so.4
#23 0x2c692b9b in ~ScrollBar (this=0x828fee0)
    at /usr/ports/x11/kdebase4/work/kdebase-4.1.1/apps/plasma/applets/folderview/folderview.cpp:70
#24 0x2a3665a0 in QGraphicsItem::~QGraphicsItem ()
   from /usr/local/lib/qt4/libQtGui.so.4
#25 0x2a399ef2 in QGraphicsWidget::~QGraphicsWidget ()
   from /usr/local/lib/qt4/libQtGui.so.4
#26 0x2813a488 in ~Applet (this=0x818c360)
    at /usr/ports/x11/kdebase4-workspace/work/kdebase-workspace-4.1.1/libs/plasma/applet.cpp:128
#27 0x2816a8af in ~Containment (this=0x818c360)
    at /usr/ports/x11/kdebase4-workspace/work/kdebase-workspace-4.1.1/libs/plasma/containment.cpp:108
#28 0x2c68b100 in ~FolderView (this=0x818c360)
    at /usr/ports/x11/kdebase4/work/kdebase-4.1.1/apps/plasma/applets/folderview/folderview.cpp:188
#29 0x29907fbc in qDeleteInEventHandler ()
   from /usr/local/lib/qt4/libQtCore.so.4
#30 0x2990a961 in QObject::event () from /usr/local/lib/qt4/libQtCore.so.4
#31 0x2a39c950 in QGraphicsWidget::event ()
   from /usr/local/lib/qt4/libQtGui.so.4
#32 0x29e7aafc in QApplicationPrivate::notify_helper ()
   from /usr/local/lib/qt4/libQtGui.so.4
#33 0x29e814be in QApplication::notify ()
   from /usr/local/lib/qt4/libQtGui.so.4
#34 0x28773ba3 in KApplication::notify (this=0x81330d0, receiver=0x818c360, 
    event=0x8450910)
    at /usr/ports/x11/kdelibs4/work/kdelibs-4.1.1/kdeui/kernel/kapplication.cpp:311
#35 0x298fb459 in QCoreApplication::notifyInternal ()
   from /usr/local/lib/qt4/libQtCore.so.4
#36 0x298fc6af in QCoreApplicationPrivate::sendPostedEvents ()
   from /usr/local/lib/qt4/libQtCore.so.4
#37 0x298fc88d in QCoreApplication::sendPostedEvents ()
   from /usr/local/lib/qt4/libQtCore.so.4
#38 0x29effef8 in QEventDispatcherX11::processEvents ()
   from /usr/local/lib/qt4/libQtGui.so.4
#39 0x298fa5d3 in QEventLoop::processEvents ()
   from /usr/local/lib/qt4/libQtCore.so.4
#40 0x298fa761 in QEventLoop::exec () from /usr/local/lib/qt4/libQtCore.so.4
#41 0x298fc94a in QCoreApplication::exec ()
   from /usr/local/lib/qt4/libQtCore.so.4
#42 0x29e7a097 in QApplication::exec () from /usr/local/lib/qt4/libQtGui.so.4
#43 0x28095d18 in kdemain (argc=1, argv=0xbfbfea98)
    at /usr/ports/x11/kdebase4-workspace/work/kdebase-workspace-4.1.1/plasma/plasma/main.cpp:58
#44 0x08048812 in main (argc=)
    at /usr/ports/x11/kdebase4-workspace/work/kdebase-workspace-4.1.1/build/plasma/plasma/plasma_qgv_dummy.cpp:3

Thread 3 (Thread 0x81abb00 (LWP 100139)):
#0  0x299b5037 in __error () from /lib/libthr.so.3
#1  0x299b4d9a in __error () from /lib/libthr.so.3
#2  0x0828a760 in ?? ()
#3  0x00000008 in ?? ()
#4  0x00000001 in ?? ()
#5  0x0828a740 in ?? ()
#6  0x00000000 in ?? ()
#7  0x299b696c in ?? () from /lib/libthr.so.3
#8  0xbf9fedd8 in ?? ()
#9  0x299b354e in pthread_cond_init () from /lib/libthr.so.3
#0  0x299b5037 in __error () from /lib/libthr.so.3

*** This bug has been marked as a duplicate of bug 172671 ***