Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.2.95 (KDE 4.2.95 (KDE 4.3 RC1))
Qt Version: 4.5.0
Operating System: Linux 2.6.28-13-generic i686
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
It has happened to me several times. I open Dolphin, click on a rar file, ark opens up. Then I extract the files. After ark finishes extracting, Plasma crashes	

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 3341)]

Thread 2 (Thread 0xa93c7b90 (LWP 3346)):
#0  0xb7f86430 in __kernel_vsyscall ()
#1  0xb64520e5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0xb66322ed in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0xb7d859b2 in QWaitCondition::wait (this=0x98e7778, mutex=0x98e7774, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#4  0xb76c1152 in QHostInfoAgent::run (this=0x98e7768) at kernel/qhostinfo.cpp:260
#5  0xb7d8496e in QThreadPrivate::start (arg=0x98e7768) at thread/qthread_unix.cpp:189
#6  0xb644e4ff in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0xb662349e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb5f5ca10 (LWP 3341)):
[KCrash Handler]
#6  0xa95c032a in TaskManager::GroupManager::manualSortingRequest () from /usr/lib/libtaskmanager.so.4
#7  0xa95be31b in TaskManager::AbstractGroupingStrategy::closeGroup () from /usr/lib/libtaskmanager.so.4
#8  0xa95c5f27 in ?? () from /usr/lib/libtaskmanager.so.4
#9  0xa95c6e5b in ?? () from /usr/lib/libtaskmanager.so.4
#10 0xb7e8eca8 in QMetaObject::activate (sender=0xa65d2a8, from_signal_index=22, to_signal_index=22, argv=0xbf9a0f2c) at kernel/qobject.cpp:3069
#11 0xb7e8f932 in QMetaObject::activate (sender=0xa65d2a8, m=0xa95e8b74, local_signal_index=1, argv=0xbf9a0f2c) at kernel/qobject.cpp:3143
#12 0xa95d9d83 in TaskManager::TaskGroup::itemRemoved () from /usr/lib/libtaskmanager.so.4
#13 0xa95da7ab in TaskManager::TaskGroup::remove () from /usr/lib/libtaskmanager.so.4
#14 0xa95c0ba5 in ?? () from /usr/lib/libtaskmanager.so.4
#15 0xa95c346a in TaskManager::GroupManager::qt_metacall () from /usr/lib/libtaskmanager.so.4
#16 0xb7e8eca8 in QMetaObject::activate (sender=0x96c3ff8, from_signal_index=5, to_signal_index=5, argv=0xbf9a10bc) at kernel/qobject.cpp:3069
#17 0xb7e8f932 in QMetaObject::activate (sender=0x96c3ff8, m=0xa95e8d3c, local_signal_index=1, argv=0xbf9a10bc) at kernel/qobject.cpp:3143
#18 0xa95dd823 in TaskManager::TaskManager::taskRemoved () from /usr/lib/libtaskmanager.so.4
#19 0xa95df0cf in TaskManager::TaskManager::windowRemoved () from /usr/lib/libtaskmanager.so.4
#20 0xa95e0fec in TaskManager::TaskManager::qt_metacall () from /usr/lib/libtaskmanager.so.4
#21 0xb7e8eca8 in QMetaObject::activate (sender=0x95d8520, from_signal_index=6, to_signal_index=6, argv=0xbf9a122c) at kernel/qobject.cpp:3069
#22 0xb7e8f932 in QMetaObject::activate (sender=0x95d8520, m=0xb75f726c, local_signal_index=2, argv=0xbf9a122c) at kernel/qobject.cpp:3143
#23 0xb758f853 in KWindowSystem::windowRemoved (this=0x95d8520, _t1=50332824) at /build/buildd/kde4libs-4.2.95/obj-i486-linux-gnu/kdeui/kwindowsystem.moc:127
#24 0xb75920d6 in KWindowSystemPrivate::removeClient (this=0x951e9e0, w=50332824) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/kwindowsystem_x11.cpp:249
#25 0xb75a1753 in NETRootInfo::update (this=0x951e9f4, dirty_props=0xbf9a1374) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/netwm.cpp:2135
#26 0xb75a1b3f in NETRootInfo::event (this=0x951e9f4, event=0xbf9a1a8c, properties=0xbf9a1458, properties_size=5) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/netwm.cpp:2058
#27 0xb759236d in KWindowSystemPrivate::x11Event (this=0x951e9e0, ev=0xbf9a1a2c) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/kwindowsystem_x11.cpp:136
#28 0xb74426f9 in KApplication::x11EventFilter (this=0x9401db8, _event=0xbf9a1a2c) at /build/buildd/kde4libs-4.2.95/kdeui/kernel/kapplication.cpp:911
#29 0xb4ab2e37 in ?? () from /usr/lib/libkdeinit4_plasma-desktop.so
#30 0xb696bf3e in qt_x11EventFilter (ev=0xbf9a1a2c) at kernel/qapplication_x11.cpp:375
#31 0xb697e6a8 in QApplication::x11ProcessEvent (this=0x9401db8, event=0xbf9a1a2c) at kernel/qapplication_x11.cpp:3273
#32 0xb69aac6a in x11EventSourceDispatch (s=0x940aa70, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#33 0xb649bb88 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#34 0xb649f0eb in ?? () from /usr/lib/libglib-2.0.so.0
#35 0xb649f268 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#36 0xb7ea4438 in QEventDispatcherGlib::processEvents (this=0x9405520, flags={i = -1080419352}) at kernel/qeventdispatcher_glib.cpp:323
#37 0xb69aa365 in QGuiEventDispatcherGlib::processEvents (this=0x9405520, flags={i = -1080419304}) at kernel/qguieventdispatcher_glib.cpp:202
#38 0xb7e7706a in QEventLoop::processEvents (this=0xbf9a1c90, flags={i = -1080419240}) at kernel/qeventloop.cpp:149
#39 0xb7e774aa in QEventLoop::exec (this=0xbf9a1c90, flags={i = -1080419176}) at kernel/qeventloop.cpp:200
#40 0xb7e79959 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#41 0xb6908d17 in QApplication::exec () at kernel/qapplication.cpp:3553
#42 0xb4a9d510 in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#43 0x0804e1c0 in launch (argc=1, _name=0x93cf464 "/usr/bin/plasma-desktop", args=0x93cf47c "", cwd=0x0, envc=0, envs=0x93cf480 "", reset_env=false, tty=0x0, avoid_loops=false, 
    startup_id_str=0x80512d1 "0") at /build/buildd/kde4libs-4.2.95/kinit/kinit.cpp:672
#44 0x0804e99d in handle_launcher_request (sock=7, who=<value optimized out>) at /build/buildd/kde4libs-4.2.95/kinit/kinit.cpp:1164
#45 0x0804ef25 in handle_requests (waitForPid=0) at /build/buildd/kde4libs-4.2.95/kinit/kinit.cpp:1357
#46 0x0804fb0a in main (argc=2, argv=0xbf9a2484, envp=0xbf9a2490) at /build/buildd/kde4libs-4.2.95/kinit/kinit.cpp:1784

Reported using DrKonqi