Version:            (using KDE 4.2.3)
Installed from:    Gentoo Packages

I'm not able to say if it same than another bug:

Application: Plasma Workspace (plasma), signal SIGSEGV
0x00007f0e87a9b8d1 in nanosleep () from /lib/libc.so.6
Current language:  auto; currently c
[Current thread is 0 (LWP 5128)]

Thread 3 (Thread 0x7f0e70ceb950 (LWP 5371)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00007f0e8aada665 in QWaitCondition::wait (this=0x26707b0, mutex=0x26707a8, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:87
#2  0x00007f0e72f4915e in RenderThread::run (this=0x2670798) at /var/tmp/portage/kde-base/plasma-workspace-4.2.3/work/plasma-workspace-4.2.3/plasma/wallpapers/image/renderthread.cpp:91
#3  0x00007f0e8aad9ac9 in QThreadPrivate::start (arg=0x2670798) at thread/qthread_unix.cpp:189
#4  0x00007f0e8a867007 in start_thread (arg=<value optimized out>) at pthread_create.c:297
#5  0x00007f0e87acbf4d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f0e6bfff950 (LWP 5435)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00007f0e8aada665 in QWaitCondition::wait (this=0x24d2be0, mutex=0x24d2bd8, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:87
#2  0x00007f0e8c08a64c in QHostInfoAgent::run (this=0x24d2bc0) at kernel/qhostinfo.cpp:260
#3  0x00007f0e8aad9ac9 in QThreadPrivate::start (arg=0x24d2bc0) at thread/qthread_unix.cpp:189
#4  0x00007f0e8a867007 in start_thread (arg=<value optimized out>) at pthread_create.c:297
#5  0x00007f0e87acbf4d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()
Current language:  auto; currently asm

Thread 1 (Thread 0x7f0e8d573760 (LWP 5128)):
[KCrash Handler]
#5  QHashData::nextNode (node=0x28b8770) at tools/qhash.cpp:228
#6  0x00007f0e71decba5 in TaskManager::GroupManager::add (this=0x29eab10, task={d = 0x7fff955b7ad0}) at /usr/include/qt4/QtCore/qhash.h:335
#7  0x00007f0e71deeccb in TaskManager::GroupManager::qt_metacall (this=0x29eab10, _c=<value optimized out>, _id=<value optimized out>, _a=0x7fff955b7c00)
    at /var/tmp/portage/kde-base/libtaskmanager-4.2.3/work/libtaskmanager_build/libs/taskmanager/groupmanager.moc:91
#8  0x00007f0e8abce2fd in QMetaObject::activate (sender=0x2a555f0, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x1) at kernel/qobject.cpp:3108
#9  0x00007f0e71e05bb2 in TaskManager::TaskManager::taskAdded (this=0x28b8770, _t1=<value optimized out>)
    at /var/tmp/portage/kde-base/libtaskmanager-4.2.3/work/libtaskmanager_build/libs/taskmanager/taskmanager.moc:152
#10 0x00007f0e71e07e47 in TaskManager::TaskManager::windowAdded (this=0x2a555f0, w=60817497)
    at /var/tmp/portage/kde-base/libtaskmanager-4.2.3/work/libtaskmanager-4.2.3/libs/taskmanager/taskmanager.cpp:248
#11 0x00007f0e71e08edf in TaskManager::TaskManager::qt_metacall (this=0x2a555f0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff955b7ea0)
    at /var/tmp/portage/kde-base/libtaskmanager-4.2.3/work/libtaskmanager_build/libs/taskmanager/taskmanager.moc:107
#12 0x00007f0e8abce2fd in QMetaObject::activate (sender=0x254e380, from_signal_index=<value optimized out>, to_signal_index=5, argv=0x1) at kernel/qobject.cpp:3108
#13 0x00007f0e8b8cfd72 in KWindowSystem::windowAdded (this=0x28b8770, _t1=60817497) at /var/tmp/portage/kde-base/kdelibs-4.2.3/work/kdelibs_build/kdeui/kwindowsystem.moc:120
#14 0x00007f0e8b8d2014 in KWindowSystemPrivate::addClient (this=0x254e860, w=60817497) at /var/tmp/portage/kde-base/kdelibs-4.2.3/work/kdelibs-4.2.3/kdeui/windowmanagement/kwindowsystem_x11.cpp:229
#15 0x00007f0e8b8e0c0b in NETRootInfo::update (this=0x254e888, dirty_props=<value optimized out>) at /var/tmp/portage/kde-base/kdelibs-4.2.3/work/kdelibs-4.2.3/kdeui/windowmanagement/netwm.cpp:2123
#16 0x00007f0e8b8e0f59 in NETRootInfo::event (this=0x254e888, event=<value optimized out>, properties=0x7fff955b81b0, properties_size=5)
    at /var/tmp/portage/kde-base/kdelibs-4.2.3/work/kdelibs-4.2.3/kdeui/windowmanagement/netwm.cpp:2052
#17 0x00007f0e8b8d247b in KWindowSystemPrivate::x11Event (this=0x254e860, ev=0x7fff955b9be0)
    at /var/tmp/portage/kde-base/kdelibs-4.2.3/work/kdelibs-4.2.3/kdeui/windowmanagement/kwindowsystem_x11.cpp:136
#18 0x00007f0e8b79cf23 in KApplication::x11EventFilter (this=<value optimized out>, _event=0x7fff955b9be0)
    at /var/tmp/portage/kde-base/kdelibs-4.2.3/work/kdelibs-4.2.3/kdeui/kernel/kapplication.cpp:935
#19 0x00007f0e8d161ec1 in PlasmaApp::x11EventFilter (this=0x2468180, event=0x7fff955b9be0)
    at /var/tmp/portage/kde-base/plasma-workspace-4.2.3/work/plasma-workspace-4.2.3/plasma/shells/desktop/plasmaapp.cpp:453
#20 0x00007f0e89c991cf in qt_x11EventFilter (ev=0x7fff955b9be0) at kernel/qapplication_x11.cpp:375
#21 0x00007f0e89ca6ac1 in QApplication::x11ProcessEvent (this=0x2468180, event=0x7fff955b9be0) at kernel/qapplication_x11.cpp:3287
#22 0x00007f0e89cccf7c in x11EventSourceDispatch (s=0x2473850, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#23 0x00007f0e84bd5232 in IA__g_main_context_dispatch (context=0x2472c40) at gmain.c:2144
#24 0x00007f0e84bd894d in g_main_context_iterate (context=0x2472c40, block=1, dispatch=1, self=<value optimized out>) at gmain.c:2778
#25 0x00007f0e84bd8b0b in IA__g_main_context_iteration (context=0x2472c40, may_block=1) at gmain.c:2841
#26 0x00007f0e8abe07ff in QEventDispatcherGlib::processEvents (this=0x2470270, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:324
#27 0x00007f0e89ccc7df in QGuiEventDispatcherGlib::processEvents (this=0x28b8770, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#28 0x00007f0e8abb7932 in QEventLoop::processEvents (this=<value optimized out>, flags={i = -1789157680}) at kernel/qeventloop.cpp:149
#29 0x00007f0e8abb7ac5 in QEventLoop::exec (this=0x7fff955b9f10, flags={i = -1789157600}) at kernel/qeventloop.cpp:196
#30 0x00007f0e8abbc686 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#31 0x00007f0e8d15128b in kdemain (argc=1, argv=0x7fff955ba218) at /var/tmp/portage/kde-base/plasma-workspace-4.2.3/work/plasma-workspace-4.2.3/plasma/shells/desktop/main.cpp:54
#32 0x00007f0e87a1a5c6 in __libc_start_main (main=0x4009f0 <main>, argc=1, ubp_av=0x7fff955ba218, init=0x400a20 <__libc_csu_init>, fini=<value optimized out>, rtld_fini=<value optimized out>, 
    stack_end=0x7fff955ba208) at libc-start.c:226
#33 0x0000000000400929 in _start () at ../sysdeps/x86_64/elf/start.S:113
#0  0x00007f0e87a9b8d1 in nanosleep () from /lib/libc.so.6
Current language:  auto; currently c