Version:            (using KDE 4.2.3)
OS:                Linux
Installed from:    Ubuntu Packages

Click the clock to get the calendar widget. Start dragging it. It gets detached, but won't actually move. Try moving it again. Plasma crashes:

Application: Plasma Workspace (plasma), signal SIGSEGV
[Current thread is 0 (LWP 7423)]

Thread 3 (Thread 0xa8613b90 (LWP 7424)):
#0  0xb809e430 in __kernel_vsyscall ()
#1  0xb51de0e5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0xb63ed2ed in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0xb65d99b2 in QWaitCondition::wait (this=0x9174a10, mutex=0x9174a0c, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#4  0xb7a5c152 in QHostInfoAgent::run (this=0x9174a00) at kernel/qhostinfo.cpp:260
#5  0xb65d896e in QThreadPrivate::start (arg=0x9174a00) at thread/qthread_unix.cpp:189
#6  0xb51da4ff in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0xb63de49e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 2 (Thread 0xa7de8b90 (LWP 7425)):
#0  0xb809e430 in __kernel_vsyscall ()
#1  0xb51de0e5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0xb63ed2ed in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0xb65d99b2 in QWaitCondition::wait (this=0x8e0b2a8, mutex=0x8e0b2a4, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#4  0xa8730b9a in ?? () from /usr/lib/kde4/plasma_wallpaper_image.so
#5  0xb65d896e in QThreadPrivate::start (arg=0xa6f05df0) at thread/qthread_unix.cpp:189
#6  0xb51da4ff in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0xb63de49e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb3dc4730 (LWP 7423)):
[KCrash Handler]
#6  QMetaObject::cast (this=0xb72157cc, obj=0x1) at kernel/qmetaobject.cpp:299
#7  0xb6fdcc3b in QGraphicsScenePrivate::itemsAtPosition (this=0x8de6c90, screenPos=@0xbfdbabe4, scenePos=@0xbfdbabd0, widget=0x8d99018) at ../../include/QtCore/../../src/corelib/kernel/qobject.h:443
#8  0xb6fdd4bf in QGraphicsScenePrivate::dispatchHoverEvent (this=0x8de6c90, hoverEvent=0xbfdbac48) at graphicsview/qgraphicsscene.cpp:4070
#9  0xb6fdd615 in QGraphicsScene::mouseReleaseEvent (this=0x8de8e80, mouseEvent=0xbfdbb084) at graphicsview/qgraphicsscene.cpp:4314
#10 0xb6fdd93a in QGraphicsScene::event (this=0x8de8e80, event=0xbfdbb084) at graphicsview/qgraphicsscene.cpp:3661
#11 0xb6979f2c in QApplicationPrivate::notify_helper (this=0x8d32118, receiver=0x8de8e80, e=0xbfdbb084) at kernel/qapplication.cpp:4084
#12 0xb698222e in QApplication::notify (this=0x8d15520, receiver=0x8de8e80, e=0xbfdbb084) at kernel/qapplication.cpp:3631
#13 0xb77d3e5d in KApplication::notify (this=0x8d15520, receiver=0x8de8e80, event=0xbfdbb084) at /build/buildd/kde4libs-4.2.3/kdeui/kernel/kapplication.cpp:307
#14 0xb66cca3b in QCoreApplication::notifyInternal (this=0x8d15520, receiver=0x8de8e80, event=0xbfdbb084) at kernel/qcoreapplication.cpp:602
#15 0xb6ff2bb2 in QGraphicsView::mouseReleaseEvent (this=0x92f1ff0, event=0xbfdbb688) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#16 0xb69d0bd3 in QWidget::event (this=0x92f1ff0, event=0xbfdbb688) at kernel/qwidget.cpp:7516
#17 0xb6daad83 in QFrame::event (this=0x92f1ff0, e=0xbfdbb688) at widgets/qframe.cpp:559
#18 0xb6e4ad3f in QAbstractScrollArea::viewportEvent (this=0x92f1ff0, e=0x8d99018) at widgets/qabstractscrollarea.cpp:962
#19 0xb6fee4f2 in QGraphicsView::viewportEvent (this=0x92f1ff0, event=0xbfdbb688) at graphicsview/qgraphicsview.cpp:2933
#20 0xb6e4d345 in QAbstractScrollAreaFilter::eventFilter (this=0x9ff7bc8, o=0x8d99018, e=0xbfdbb688) at widgets/qabstractscrollarea_p.h:100
#21 0xb66cbc5a in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=0x8d32118, receiver=0x8d99018, event=0xbfdbb688) at kernel/qcoreapplication.cpp:718
#22 0xb6979f0a in QApplicationPrivate::notify_helper (this=0x8d32118, receiver=0x8d99018, e=0xbfdbb688) at kernel/qapplication.cpp:4080
#23 0xb6982ba1 in QApplication::notify (this=0x8d15520, receiver=0x8d99018, e=0xbfdbb688) at kernel/qapplication.cpp:3786
#24 0xb77d3e5d in KApplication::notify (this=0x8d15520, receiver=0x8d99018, event=0xbfdbb688) at /build/buildd/kde4libs-4.2.3/kdeui/kernel/kapplication.cpp:307
#25 0xb66cca3b in QCoreApplication::notifyInternal (this=0x8d15520, receiver=0x8d99018, event=0xbfdbb688) at kernel/qcoreapplication.cpp:602
#26 0xb6981c0e in QApplicationPrivate::sendMouseEvent (receiver=0x8d99018, event=0xbfdbb688, alienWidget=0x8d99018, nativeWidget=0x92f1ff0, buttonDown=0xb7225200, lastMouseReceiver=@0xb7225204)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#27 0xb69f1a0e in QETWidget::translateMouseEvent (this=0x92f1ff0, event=0xbfdbbccc) at kernel/qapplication_x11.cpp:4425
#28 0xb69f0d37 in QApplication::x11ProcessEvent (this=0x8d15520, event=0xbfdbbccc) at kernel/qapplication_x11.cpp:3421
#29 0xb6a1bcfa in x11EventSourceDispatch (s=0x8d36908, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#30 0xb4fd8b88 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#31 0xb4fdc0eb in ?? () from /usr/lib/libglib-2.0.so.0
#32 0xb4fdc268 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#33 0xb66f8438 in QEventDispatcherGlib::processEvents (this=0x8cf7488, flags={i = -1076117880}) at kernel/qeventdispatcher_glib.cpp:323
#34 0xb6a1b3f5 in QGuiEventDispatcherGlib::processEvents (this=0x8cf7488, flags={i = -1076117832}) at kernel/qguieventdispatcher_glib.cpp:202
#35 0xb66cb06a in QEventLoop::processEvents (this=0xbfdbbf30, flags={i = -1076117768}) at kernel/qeventloop.cpp:149
#36 0xb66cb4aa in QEventLoop::exec (this=0xbfdbbf30, flags={i = -1076117704}) at kernel/qeventloop.cpp:200
#37 0xb66cd959 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#38 0xb6979da7 in QApplication::exec () at kernel/qapplication.cpp:3553
#39 0xb8047b56 in kdemain () from /usr/lib/libkdeinit4_plasma.so
#40 0x08048712 in _start ()