Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.2
Operating System: Linux 2.6.31.1 x86_64
Distribution: Debian GNU/Linux 4.3 (n/a)

What I was doing when the application crashed:
When openig a new window of already running program, taskbar seems to loose config to default settings. After a few seconds it restarts due to crash. I am sorry but there is no libc6-dbg available with apt. Error message: 
E: Failed to fetch http://ftp.pl.debian.org/debian/pool/main/e/eglibc/libc6-dbg_2.9-26_amd64.deb: 404  Not Found
If You know what to install correctly maybe by adding extra server or using mirror please contact me.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f8d4e760750 (LWP 5035))]

Thread 2 (Thread 0x7f8d2f56f950 (LWP 5038)):
#0  0x00007f8d4afe0b89 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007f8d4e2a1469 in QWaitConditionPrivate::wait (this=0x23d8380, mutex=0x23d8378, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:87
#2  QWaitCondition::wait (this=0x23d8380, mutex=0x23d8378, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:159
#3  0x00007f8d4a69b024 in QHostInfoAgent::run (this=0x23d8360) at kernel/qhostinfo.cpp:260
#4  0x00007f8d4e2a0475 in QThreadPrivate::start (arg=0x23d8360) at thread/qthread_unix.cpp:188
#5  0x00007f8d4afdcf9a in start_thread () from /lib/libpthread.so.0
#6  0x00007f8d4bba556d in clone () from /lib/libc.so.6
#7  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f8d4e760750 (LWP 5035)):
[KCrash Handler]
#5  0x00007f8d4c8f0544 in QGraphicsLayoutItem::geometry (this=0x239e7c0) at graphicsview/qgraphicslayoutitem.cpp:664
#6  0x00007f8d4c8f3f25 in QGraphicsWidget::size (this=<value optimized out>) at graphicsview/qgraphicswidget.cpp:336
#7  0x00007f8d3112fdfe in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#8  0x00007f8d3112c366 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#9  0x00007f8d3112ccdc in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#10 0x00007f8d3112cd6b in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#11 0x00007f8d3112d709 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#12 0x00007f8d3112d7ae in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#13 0x00007f8d311386d9 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#14 0x00007f8d31139ae1 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#15 0x00007f8d4e39b682 in QMetaObject::activate (sender=0x216e300, from_signal_index=<value optimized out>, to_signal_index=22, argv=0x0) at kernel/qobject.cpp:3112
#16 0x00007f8d31373442 in TaskManager::TaskGroup::itemRemoved(TaskManager::AbstractGroupableItem*) () from /usr/lib/libtaskmanager.so.4
#17 0x00007f8d31373d51 in TaskManager::TaskGroup::remove(TaskManager::AbstractGroupableItem*) () from /usr/lib/libtaskmanager.so.4
#18 0x00007f8d3135d544 in ?? () from /usr/lib/libtaskmanager.so.4
#19 0x00007f8d3135da7e in ?? () from /usr/lib/libtaskmanager.so.4
#20 0x00007f8d3135ecd2 in TaskManager::GroupManager::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libtaskmanager.so.4
#21 0x00007f8d4e39b682 in QMetaObject::activate (sender=0x216e2b8, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x0) at kernel/qobject.cpp:3112
#22 0x00007f8d4e395bf3 in QObject::event (this=0x216e2b8, e=0x239e7c0) at kernel/qobject.cpp:1074
#23 0x00007f8d4c31180d in QApplicationPrivate::notify_helper (this=0x1cd4a50, receiver=0x216e2b8, e=0x7fff13dec400) at kernel/qapplication.cpp:4056
#24 0x00007f8d4c31986a in QApplication::notify (this=0x1ccbc20, receiver=0x216e2b8, e=0x7fff13dec400) at kernel/qapplication.cpp:4021
#25 0x00007f8d4cf6b43b in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#26 0x00007f8d4e38651c in QCoreApplication::notifyInternal (this=0x1ccbc20, receiver=0x216e2b8, event=0x7fff13dec400) at kernel/qcoreapplication.cpp:610
#27 0x00007f8d4e3b2826 in QCoreApplication::sendEvent (this=0x1cd83a0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#28 QTimerInfoList::activateTimers (this=0x1cd83a0) at kernel/qeventdispatcher_unix.cpp:572
#29 0x00007f8d4e3aec9d in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:165
#30 0x00007f8d4b22c12a in g_main_dispatch (context=0x1cd7480) at /tmp/buildd/glib2.0-2.22.0/glib/gmain.c:1960
#31 IA__g_main_context_dispatch (context=0x1cd7480) at /tmp/buildd/glib2.0-2.22.0/glib/gmain.c:2513
#32 0x00007f8d4b22f988 in g_main_context_iterate (context=0x1cd7480, block=1, dispatch=1, self=<value optimized out>) at /tmp/buildd/glib2.0-2.22.0/glib/gmain.c:2591
#33 0x00007f8d4b22fb3c in IA__g_main_context_iteration (context=0x1cd7480, may_block=1) at /tmp/buildd/glib2.0-2.22.0/glib/gmain.c:2654
#34 0x00007f8d4e3aebff in QEventDispatcherGlib::processEvents (this=0x1cd4320, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:327
#35 0x00007f8d4c3a864f in QGuiEventDispatcherGlib::processEvents (this=0x7fff13deb540, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#36 0x00007f8d4e384de2 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#37 0x00007f8d4e3851b4 in QEventLoop::exec (this=0x7fff13dec6b0, flags=...) at kernel/qeventloop.cpp:201
#38 0x00007f8d4e387424 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#39 0x00007f8d4253226b in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#40 0x0000000000407264 in _start ()

Reported using DrKonqi