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 2.6.30-020630-generic i686
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
Usually when I use Virtualbox 3.0 and start some guest os'es, plasma-desktop crached every 10-30 minutes.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 3982)]

Thread 2 (Thread 0xa92fcb90 (LWP 3987)):
#0  0xb7ffb430 in __kernel_vsyscall ()
#1  0xb64c80e5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2  0xb66a82ed in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3  0xb7dfb9b2 in QWaitCondition::wait (this=0x991ad50, mutex=0x991ad4c, time=4294967295) at thread/qwaitcondition_unix.cpp:87
#4  0xb7737152 in QHostInfoAgent::run (this=0x991ad40) at kernel/qhostinfo.cpp:260
#5  0xb7dfa96e in QThreadPrivate::start (arg=0x991ad40) at thread/qthread_unix.cpp:189
#6  0xb64c44ff in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0xb669949e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb5fd2a10 (LWP 3982)):
[KCrash Handler]
#6  TaskManager::GroupManager::manualSortingRequest (this=0x0, taskItem=0x99c0ad8, newIndex=2) at /build/buildd/kdebase-workspace-4.2.95/libs/taskmanager/groupmanager.cpp:363
#7  0xa955c31b in TaskManager::AbstractGroupingStrategy::closeGroup (this=0x95ecce8, group=0x9c02180) at /build/buildd/kdebase-workspace-4.2.95/libs/taskmanager/abstractgroupingstrategy.cpp:167
#8  0xa9563f27 in TaskManager::ProgramGroupingStrategy::checkGroup (this=0x95ecce8) at /build/buildd/kdebase-workspace-4.2.95/libs/taskmanager/strategies/programgroupingstrategy.cpp:204
#9  0xa9564e5b in TaskManager::ProgramGroupingStrategy::qt_metacall (this=0x95ecce8, _c=QMetaObject::InvokeMetaMethod, _id=0, _a=0xbfc342bc)
    at /build/buildd/kdebase-workspace-4.2.95/obj-i486-linux-gnu/libs/taskmanager/programgroupingstrategy.moc:68
#10 0xb7f04ca8 in QMetaObject::activate (sender=0x9c02180, from_signal_index=22, to_signal_index=22, argv=0xbfc342bc) at kernel/qobject.cpp:3069
#11 0xb7f05932 in QMetaObject::activate (sender=0x9c02180, m=0xa9586b74, local_signal_index=1, argv=0xbfc342bc) at kernel/qobject.cpp:3143
#12 0xa9577d83 in TaskManager::TaskGroup::itemRemoved (this=0x9c02180, _t1=0x9da46c8) at /build/buildd/kdebase-workspace-4.2.95/obj-i486-linux-gnu/libs/taskmanager/taskgroup.moc:146
#13 0xa95787ab in TaskManager::TaskGroup::remove (this=0x9c02180, item=0x9da46c8) at /build/buildd/kdebase-workspace-4.2.95/libs/taskmanager/taskgroup.cpp:182
#14 0xa955eba5 in TaskManager::GroupManagerPrivate::removeTask (this=0x95ba098, task={d = 0xbfc3436c}) at /build/buildd/kdebase-workspace-4.2.95/libs/taskmanager/groupmanager.cpp:311
#15 0xa956146a in TaskManager::GroupManager::qt_metacall (this=0x95ba708, _c=QMetaObject::InvokeMetaMethod, _id=11, _a=0xbfc3444c)
    at /build/buildd/kdebase-workspace-4.2.95/obj-i486-linux-gnu/libs/taskmanager/groupmanager.moc:105
#16 0xb7f04ca8 in QMetaObject::activate (sender=0x95ddc98, from_signal_index=5, to_signal_index=5, argv=0xbfc3444c) at kernel/qobject.cpp:3069
#17 0xb7f05932 in QMetaObject::activate (sender=0x95ddc98, m=0xa9586d3c, local_signal_index=1, argv=0xbfc3444c) at kernel/qobject.cpp:3143
#18 0xa957b823 in TaskManager::TaskManager::taskRemoved (this=0x95ddc98, _t1={d = 0xbfc34494}) at /build/buildd/kdebase-workspace-4.2.95/obj-i486-linux-gnu/libs/taskmanager/taskmanager.moc:162
#19 0xa957d0cf in TaskManager::TaskManager::windowRemoved (this=0x95ddc98, w=41946746) at /build/buildd/kdebase-workspace-4.2.95/libs/taskmanager/taskmanager.cpp:279
#20 0xa957efec in TaskManager::TaskManager::qt_metacall (this=0x95ddc98, _c=QMetaObject::InvokeMetaMethod, _id=7, _a=0xbfc345bc)
    at /build/buildd/kdebase-workspace-4.2.95/obj-i486-linux-gnu/libs/taskmanager/taskmanager.moc:110
#21 0xb7f04ca8 in QMetaObject::activate (sender=0x94c8fd8, from_signal_index=6, to_signal_index=6, argv=0xbfc345bc) at kernel/qobject.cpp:3069
#22 0xb7f05932 in QMetaObject::activate (sender=0x94c8fd8, m=0xb766d26c, local_signal_index=2, argv=0xbfc345bc) at kernel/qobject.cpp:3143
#23 0xb7605853 in KWindowSystem::windowRemoved (this=0x94c8fd8, _t1=41946746) at /build/buildd/kde4libs-4.2.95/obj-i486-linux-gnu/kdeui/kwindowsystem.moc:127
#24 0xb76080d6 in KWindowSystemPrivate::removeClient (this=0x92e0ad0, w=41946746) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/kwindowsystem_x11.cpp:249
#25 0xb7617753 in NETRootInfo::update (this=0x92e0ae4, dirty_props=0xbfc34704) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/netwm.cpp:2135
#26 0xb7617b3f in NETRootInfo::event (this=0x92e0ae4, event=0xbfc34e1c, properties=0xbfc347e8, properties_size=5) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/netwm.cpp:2058
#27 0xb760836d in KWindowSystemPrivate::x11Event (this=0x92e0ad0, ev=0xbfc34dbc) at /build/buildd/kde4libs-4.2.95/kdeui/windowmanagement/kwindowsystem_x11.cpp:136
#28 0xb74b86f9 in KApplication::x11EventFilter (this=0x92253b0, _event=0xbfc34dbc) at /build/buildd/kde4libs-4.2.95/kdeui/kernel/kapplication.cpp:911
#29 0xb4b40e37 in PlasmaApp::x11EventFilter (this=0x92253b0, event=0xbfc34dbc) at /build/buildd/kdebase-workspace-4.2.95/plasma/shells/desktop/plasmaapp.cpp:490
#30 0xb69e1f3e in qt_x11EventFilter (ev=0xbfc34dbc) at kernel/qapplication_x11.cpp:375
#31 0xb69f46a8 in QApplication::x11ProcessEvent (this=0x92253b0, event=0xbfc34dbc) at kernel/qapplication_x11.cpp:3273
#32 0xb6a20c6a in x11EventSourceDispatch (s=0x922e070, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#33 0xb6511b88 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#34 0xb65150eb in ?? () from /usr/lib/libglib-2.0.so.0
#35 0xb6515268 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#36 0xb7f1a438 in QEventDispatcherGlib::processEvents (this=0x9228ae0, flags={i = -1077719176}) at kernel/qeventdispatcher_glib.cpp:323
#37 0xb6a20365 in QGuiEventDispatcherGlib::processEvents (this=0x9228ae0, flags={i = -1077719128}) at kernel/qguieventdispatcher_glib.cpp:202
#38 0xb7eed06a in QEventLoop::processEvents (this=0xbfc35020, flags={i = -1077719064}) at kernel/qeventloop.cpp:149
#39 0xb7eed4aa in QEventLoop::exec (this=0xbfc35020, flags={i = -1077719000}) at kernel/qeventloop.cpp:200
#40 0xb7eef959 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#41 0xb697ed17 in QApplication::exec () at kernel/qapplication.cpp:3553
#42 0xb4b2b510 in kdemain (argc=1, argv=0x91fc870) at /build/buildd/kdebase-workspace-4.2.95/plasma/shells/desktop/main.cpp:50
#43 0x0804e1c0 in launch (argc=1, _name=0x9212034 "/usr/bin/plasma-desktop", args=0x921204c "", cwd=0x0, envc=0, envs=0x9212050 "", 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=0xbfc35814, envp=0xbfc35820) at /build/buildd/kde4libs-4.2.95/kinit/kinit.cpp:1784

Reported using DrKonqi