Version:            (using KDE 4.2.2)
OS:                Linux
Installed from:    Fedora RPMs

I started kmix, and clicked on its entry in the task manager which caused plasma to crash:

Application: Plasma Workspace (plasma), signal SIGSEGV
__kernel_vsyscall () at arch/x86/vdso/vdso32/int80.S:16
16		ret
Current language:  auto; currently asm
[Current thread is 1 (Thread 0xb806e780 (LWP 3672))]

Thread 3 (Thread 0xacfaab70 (LWP 3676)):
#0  __kernel_vsyscall () at arch/x86/vdso/vdso32/int80.S:16
#1  0x00c1e015 in pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S:122
#2  0x0358eef7 in QWaitConditionPrivate::wait (time=<value optimized out>, this=<value optimized out>) at thread/qwaitcondition_unix.cpp:87
#3  QWaitCondition::wait (time=<value optimized out>, this=<value optimized out>) at thread/qwaitcondition_unix.cpp:159
#4  0x0397cd8a in QHostInfoAgent::run (this=0x8810168) at kernel/qhostinfo.cpp:260
#5  0x0358de8e in QThreadPrivate::start (arg=0x8810168) at thread/qthread_unix.cpp:189
#6  0x00c19965 in start_thread (arg=0xacfaab70) at pthread_create.c:297
#7  0x00b4df9e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:130

Thread 2 (Thread 0xac3ffb70 (LWP 3677)):
#0  __kernel_vsyscall () at arch/x86/vdso/vdso32/int80.S:16
#1  0x00c1e015 in pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S:122
#2  0x0358eef7 in QWaitConditionPrivate::wait (time=<value optimized out>, this=<value optimized out>) at thread/qwaitcondition_unix.cpp:87
#3  QWaitCondition::wait (time=<value optimized out>, this=<value optimized out>) at thread/qwaitcondition_unix.cpp:159
#4  0x07aa91ea in RenderThread::run (this=0x872a904) at /usr/src/debug/kdebase-workspace-4.2.2/plasma/wallpapers/image/renderthread.cpp:91
#5  0x0358de8e in QThreadPrivate::start (arg=0x872a904) at thread/qthread_unix.cpp:189
#6  0x00c19965 in start_thread (arg=0xac3ffb70) at pthread_create.c:297
#7  0x00b4df9e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:130

Thread 1 (Thread 0xb806e780 (LWP 3672)):
[KCrash Handler]
#6  0x07d2ed82 in WindowTaskItem::setAdditionalMimeData (this=0x90fab30, mimeData=0x8a1b910) at /usr/src/debug/kdebase-workspace-4.2.2/plasma/applets/tasks/windowtaskitem.cpp:298
#7  0x07d376b2 in AbstractTaskItem::mouseMoveEvent (this=0x90fab30, event=0xbfe99690) at /usr/src/debug/kdebase-workspace-4.2.2/plasma/applets/tasks/abstracttaskitem.cpp:287
#8  0x05586f70 in QGraphicsItem::sceneEvent (this=0x90fab38, event=0xbfe99690) at graphicsview/qgraphicsitem.cpp:4786
#9  0x055d362f in QGraphicsWidget::sceneEvent (this=0x90fab30, event=0xbfe99690) at graphicsview/qgraphicswidget.cpp:1089
#10 0x055ac43c in QGraphicsScenePrivate::sendEvent (this=0x8449a78, item=0x90fab38, event=0xbfe99690) at graphicsview/qgraphicsscene.cpp:1150
#11 0x055adab3 in QGraphicsScenePrivate::sendMouseEvent (this=0x8449a78, mouseEvent=0xbfe99690) at graphicsview/qgraphicsscene.cpp:1221
#12 0x055b292d in QGraphicsScene::mouseMoveEvent (this=0x84c8590, mouseEvent=0xbfe99690) at graphicsview/qgraphicsscene.cpp:4272
#13 0x055b3247 in QGraphicsScene::event (this=0x84c8590, event=0xbfe99690) at graphicsview/qgraphicsscene.cpp:3655
#14 0x04f4acfc in QApplicationPrivate::notify_helper (this=0x844ef28, receiver=0x84c8590, e=0xbfe99690) at kernel/qapplication.cpp:4084
#15 0x04f52124 in QApplication::notify (this=0x84426a8, receiver=0x84c8590, e=0xbfe99690) at kernel/qapplication.cpp:4049
#16 0x059bd4ea in KApplication::notify (this=0x84426a8, receiver=0x84c8590, event=0xbfe99690) at /usr/src/debug/kdelibs-4.2.2/kdeui/kernel/kapplication.cpp:307
#17 0x036806db in QCoreApplication::notifyInternal (this=0x84426a8, receiver=0x84c8590, event=0xbfe99690) at kernel/qcoreapplication.cpp:602
#18 0x055c291f in QCoreApplication::sendEvent (event=<value optimized out>, receiver=<value optimized out>) at ../../src/corelib/kernel/qcoreapplication.h:213
#19 QGraphicsViewPrivate::mouseMoveEventHandler (event=<value optimized out>, receiver=<value optimized out>) at graphicsview/qgraphicsview.cpp:605
#20 0x055c61d3 in QGraphicsView::mouseMoveEvent (this=0x893c218, event=0xbfe99d20) at graphicsview/qgraphicsview.cpp:3335
#21 0x04fa02e1 in QWidget::event (this=0x893c218, event=0xbfe99d20) at kernel/qwidget.cpp:7501
#22 0x0537fc93 in QFrame::event (this=0x893c218, e=0xbfe99d20) at widgets/qframe.cpp:559
#23 0x0541fcb4 in QAbstractScrollArea::viewportEvent (this=0x8a1b910, e=0x0) at widgets/qabstractscrollarea.cpp:962
#24 0x055c450f in QGraphicsView::viewportEvent (this=0x893c218, event=0xbfe99d20) at graphicsview/qgraphicsview.cpp:2933
#25 0x054222f5 in QAbstractScrollAreaPrivate::viewportEvent (event=<value optimized out>, this=<value optimized out>) at widgets/qabstractscrollarea_p.h:100
#26 QAbstractScrollAreaFilter::eventFilter (event=<value optimized out>, this=<value optimized out>) at widgets/qabstractscrollarea_p.h:111
#27 0x0367f82a in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=0x844ef28, receiver=0x893d9f8, event=0xbfe99d20) at kernel/qcoreapplication.cpp:718
#28 0x04f4acda in QApplicationPrivate::notify_helper (this=0x844ef28, receiver=0x893d9f8, e=0xbfe99d20) at kernel/qapplication.cpp:4080
#29 0x04f529fb in QApplication::notify (this=0x84426a8, receiver=0x893d9f8, e=0xbfe99d20) at kernel/qapplication.cpp:3786
#30 0x059bd4ea in KApplication::notify (this=0x84426a8, receiver=0x893d9f8, event=0xbfe99d20) at /usr/src/debug/kdelibs-4.2.2/kdeui/kernel/kapplication.cpp:307
#31 0x036806db in QCoreApplication::notifyInternal (this=0x84426a8, receiver=0x893d9f8, event=0xbfe99d20) at kernel/qcoreapplication.cpp:602
#32 0x04f51a7e in QCoreApplication::sendSpontaneousEvent (event=<value optimized out>, receiver=<value optimized out>) at ../../src/corelib/kernel/qcoreapplication.h:216
#33 QApplicationPrivate::sendMouseEvent (event=<value optimized out>, receiver=<value optimized out>) at kernel/qapplication.cpp:2940
#34 0x04fc0c40 in QETWidget::translateMouseEvent (this=0x893c218, event=0xbfe9a31c) at kernel/qapplication_x11.cpp:4425
#35 0x04fc00f2 in QApplication::x11ProcessEvent (this=0x84426a8, event=0xbfe9a31c) at kernel/qapplication_x11.cpp:3421
#36 0x04feb142 in x11EventSourceDispatch (s=0x8451470, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#37 0x00ca61e8 in g_main_dispatch (context=<value optimized out>) at gmain.c:1814
#38 IA__g_main_context_dispatch (context=<value optimized out>) at gmain.c:2367
#39 0x00ca97f8 in g_main_context_iterate (context=0x8451090, block=<value optimized out>, dispatch=1, self=0x844ea58) at gmain.c:2448
#40 0x00ca996a in IA__g_main_context_iteration (context=0x8451090, may_block=1) at gmain.c:2511
#41 0x036abbcc in QEventDispatcherGlib::processEvents (this=0x8425e50, flags={i = 36}) at kernel/qeventdispatcher_glib.cpp:323
#42 0x04fea825 in QGuiEventDispatcherGlib::processEvents (this=0x8425e50, flags={i = 36}) at kernel/qguieventdispatcher_glib.cpp:202
#43 0x0367ec69 in QEventLoop::processEvents (this=0xbfe9a614, flags=) at kernel/qeventloop.cpp:149
#44 0x0367f0b2 in QEventLoop::exec (this=0xbfe9a614, flags={i = 0}) at kernel/qeventloop.cpp:200
#45 0x0368143f in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#46 0x04f4ab77 in QApplication::exec () at kernel/qapplication.cpp:3553
#47 0x03b57746 in kdemain (argc=1, argv=0xbfe9a7f4) at /usr/src/debug/kdebase-workspace-4.2.2/plasma/shells/desktop/main.cpp:54
#48 0x080486eb in main (argc=1, argv=0xbfe9a7f4) at /usr/src/debug/kdebase-workspace-4.2.2/i586-redhat-linux-gnu/plasma/shells/desktop/plasma_qgv_dummy.cpp:3