Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.00 (KDE 4.3.0)
Qt Version: 4.5.2
Operating System: Linux 2.6.31-5-generic x86_64
Distribution: Ubuntu karmic (development branch)

What I was doing when the application crashed:
I sent a folder to the trash by pressing delete, but at the same time I moved the mouse over the icon, triggering the folder preview. Suddenly there was nothing to preview and plasma chrashed.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f9eaf225750 (LWP 4023))]

Thread 2 (Thread 0x7f9e8e581910 (LWP 4026)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00007f9eaec664db in QWaitConditionPrivate::wait (this=<value optimized out>, mutex=0x1c8c928, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:87
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x1c8c928, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:159
#3  0x00007f9eab0a177c in QHostInfoAgent::run (this=0x1c8c910) at kernel/qhostinfo.cpp:260
#4  0x00007f9eaec65425 in QThreadPrivate::start (arg=0x1c8c910) at thread/qthread_unix.cpp:188
#5  0x00007f9eab9e3a04 in start_thread (arg=<value optimized out>) at pthread_create.c:300
#6  0x00007f9eac5c55fd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f9eaf225750 (LWP 4023)):
[KCrash Handler]
#5  QGraphicsScene::drawItems (this=<value optimized out>, painter=0x7fffbdcac0d0, numItems=<value optimized out>, items=0x1, options=0x39f7510, widget=<value optimized out>)
    at graphicsview/qgraphicsscene.cpp:5020
#6  0x00007f9ead2cd95e in QGraphicsView::paintEvent (this=0x3941cb0, event=<value optimized out>) at graphicsview/qgraphicsview.cpp:3528
#7  0x00007f9eacd52730 in QWidget::event (this=0x3941cb0, event=0x7fffbdcac7f0) at kernel/qwidget.cpp:7687
#8  0x00007f9ead0ae0d6 in QFrame::event (this=0x3941cb0, e=0x7fffbdcac7f0) at widgets/qframe.cpp:559
#9  0x00007f9ead2cb6cb in QGraphicsView::viewportEvent (this=0x3941cb0, event=0x7fffbdcac7f0) at graphicsview/qgraphicsview.cpp:2919
#10 0x00007f9eaed4ae97 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<value optimized out>, receiver=0x352c470, event=0x7fffbdcac7f0) at kernel/qcoreapplication.cpp:726
#11 0x00007f9eacd03ecc in QApplicationPrivate::notify_helper (this=0x1b54c90, receiver=0x352c470, e=0x7fffbdcac7f0) at kernel/qapplication.cpp:4052
#12 0x00007f9eacd0b1ce in QApplication::notify (this=0x1b4b9c0, receiver=0x352c470, e=0x7fffbdcac7f0) at kernel/qapplication.cpp:4021
#13 0x00007f9ead93a4d6 in KApplication::notify (this=0x1b4b9c0, receiver=0x352c470, event=0x7fffbdcac7f0) at ../../kdeui/kernel/kapplication.cpp:302
#14 0x00007f9eaed4bb7c in QCoreApplication::notifyInternal (this=0x1b4b9c0, receiver=0x352c470, event=0x7fffbdcac7f0) at kernel/qcoreapplication.cpp:610
#15 0x00007f9eacd59b23 in QCoreApplication::sendSpontaneousEvent (this=0x29bf130, pdev=0x3563f18, rgn=..., offset=<value optimized out>, flags=<value optimized out>, 
    sharedPainter=<value optimized out>, backingStore=0x36062b0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#16 QWidgetPrivate::drawWidget (this=0x29bf130, pdev=0x3563f18, rgn=..., offset=<value optimized out>, flags=<value optimized out>, sharedPainter=<value optimized out>, backingStore=0x36062b0)
    at kernel/qwidget.cpp:5079
#17 0x00007f9eacd5a280 in QWidgetPrivate::paintSiblingsRecursive (this=<value optimized out>, pdev=<value optimized out>, siblings=..., index=2, rgn=<value optimized out>, 
    offset=<value optimized out>, flags=4, sharedPainter=0x0, backingStore=0x36062b0) at kernel/qwidget.cpp:5189
#18 0x00007f9eacd59793 in QWidgetPrivate::drawWidget (this=0x39de0e0, pdev=0x3563f18, rgn=..., offset=<value optimized out>, flags=<value optimized out>, sharedPainter=<value optimized out>, 
    backingStore=0x36062b0) at kernel/qwidget.cpp:5128
#19 0x00007f9eacd5a280 in QWidgetPrivate::paintSiblingsRecursive (this=<value optimized out>, pdev=<value optimized out>, siblings=..., index=3, rgn=<value optimized out>, 
    offset=<value optimized out>, flags=4, sharedPainter=0x0, backingStore=0x36062b0) at kernel/qwidget.cpp:5189
#20 0x00007f9eacd59793 in QWidgetPrivate::drawWidget (this=0x39c0ed0, pdev=0x3563f18, rgn=..., offset=<value optimized out>, flags=<value optimized out>, sharedPainter=<value optimized out>, 
    backingStore=0x36062b0) at kernel/qwidget.cpp:5128
#21 0x00007f9eacecbc0e in QWidgetBackingStore::sync (this=0x36062b0) at painting/qbackingstore.cpp:1269
#22 0x00007f9eacd4bf60 in QWidgetPrivate::syncBackingStore (this=0x39c0ed0) at kernel/qwidget.cpp:1603
#23 0x00007f9eacd52548 in QWidget::event (this=0x38ee360, event=0x3a31d20) at kernel/qwidget.cpp:7827
#24 0x00007f9eacd03efc in QApplicationPrivate::notify_helper (this=0x1b54c90, receiver=0x38ee360, e=0x3a31d20) at kernel/qapplication.cpp:4056
#25 0x00007f9eacd0b1ce in QApplication::notify (this=0x1b4b9c0, receiver=0x38ee360, e=0x3a31d20) at kernel/qapplication.cpp:4021
#26 0x00007f9ead93a4d6 in KApplication::notify (this=0x1b4b9c0, receiver=0x38ee360, event=0x3a31d20) at ../../kdeui/kernel/kapplication.cpp:302
#27 0x00007f9eaed4bb7c in QCoreApplication::notifyInternal (this=0x1b4b9c0, receiver=0x38ee360, event=0x3a31d20) at kernel/qcoreapplication.cpp:610
#28 0x00007f9eaed4c75a in QCoreApplication::sendEvent (receiver=0x0, event_type=<value optimized out>, data=0x1ab4300) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#29 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=<value optimized out>, data=0x1ab4300) at kernel/qcoreapplication.cpp:1247
#30 0x00007f9eaed74483 in QCoreApplication::sendPostedEvents (s=<value optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#31 postEventSourceDispatch (s=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:210
#32 0x00007f9eabc34a8e in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#33 0x00007f9eabc38458 in ?? () from /usr/lib/libglib-2.0.so.0
#34 0x00007f9eabc38580 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#35 0x00007f9eaed740f6 in QEventDispatcherGlib::processEvents (this=0x1ab6e70, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:327
#36 0x00007f9eacd983de in QGuiEventDispatcherGlib::processEvents (this=0x7fffbdcabbf0, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#37 0x00007f9eaed4a482 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#38 0x00007f9eaed4a854 in QEventLoop::exec (this=0x7fffbdcadbd0, flags=) at kernel/qeventloop.cpp:201
#39 0x00007f9eaed4ca09 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#40 0x00007f9ea32f543f in kdemain (argc=<value optimized out>, argv=<value optimized out>) at ../../../../plasma/shells/desktop/main.cpp:50
#41 0x0000000000406da8 in launch (argc=1, _name=<value optimized out>, args=<value optimized out>, cwd=<value optimized out>, envc=0, envs=<value optimized out>, reset_env=false, tty=0x0, 
    avoid_loops=false, startup_id_str=0x40a299 "0") at ../../kinit/kinit.cpp:676
#42 0x0000000000407aa0 in handle_launcher_request (sock=7, who=<value optimized out>) at ../../kinit/kinit.cpp:1168
#43 0x0000000000407f51 in handle_requests (waitForPid=0) at ../../kinit/kinit.cpp:1361
#44 0x0000000000408bb2 in main (argc=2, argv=<value optimized out>, envp=<value optimized out>) at ../../kinit/kinit.cpp:1788

Reported using DrKonqi