Version:            (using KDE 4.2.1)
OS:                Linux
Installed from:    Unspecified Linux

I'm runnong KDE 4.2.1 on an ArchLinux x86_64 system. My computer is a laptop HP 6510b.

Here's the bug : when I open my user session for the first time, Plasma keeps running normaly. If I don't modifiy anything in my plasmoids, the system keeps running correctly boots after boots. When I customize plasmoids settings, in the taskbar for exemple, at the next boot, I've got a crash of Plasma, and it becomes impossible to open a session.
The only solution I found at this time is to delete /home/myuser/.kde4/share/config/plasma-appletsrc to get my session open again, but I lost all my settings, and if I try to customize again, it crashes again at the next boot.

Here is the bug details provided by gdb :

Application : Espace de travail Plasma (plasma), signal SIGSEGV
0x00007f43c70d8001 in nanosleep () from /lib/libc.so.6
[Current thread is 0 (LWP 4857)]

Thread 2 (Thread 0x7f43af3c9950 (LWP 4858)):
#0  0x00007f43c7b3dd69 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007f43c7dabb09 in QWaitCondition::wait () from /usr/lib/libQtCore.so.4
#2  0x00007f43cb2f7fb4 in ?? () from /usr/lib/libQtNetwork.so.4
#3  0x00007f43c7daad79 in ?? () from /usr/lib/libQtCore.so.4
#4  0x00007f43c7b39fc7 in start_thread () from /lib/libpthread.so.0
#5  0x00007f43c71085dd in clone () from /lib/libc.so.6
#6  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f43cc623760 (LWP 4857)):
[KCrash Handler]
#5  0x00007f43c7e94401 in QTimer::stop () from /usr/lib/libQtCore.so.4
#6  0x00007f43cc31ea80 in PanelView::updatePanelGeometry () from /usr/lib/libkdeinit4_plasma.so
#7  0x00007f43cc320bf0 in PanelView::qt_metacall () from /usr/lib/libkdeinit4_plasma.so
#8  0x00007f43c7e8dd30 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#9  0x00007f43cc02a7c8 in Plasma::ViewPrivate::updateSceneRect () from /usr/lib/libplasma.so.3
#10 0x00007f43cc029e09 in Plasma::View::qt_metacall () from /usr/lib/libplasma.so.3
#11 0x00007f43cc320b95 in PanelView::qt_metacall () from /usr/lib/libkdeinit4_plasma.so
#12 0x00007f43c7e8dd30 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#13 0x00007f43cbfc03e8 in Plasma::Applet::itemChange () from /usr/lib/libplasma.so.3
#14 0x00007f43cbfcbd28 in Plasma::Containment::itemChange () from /usr/lib/libplasma.so.3
#15 0x00007f43c89da3a3 in QGraphicsItem::setPos () from /usr/lib/libQtGui.so.4
#16 0x00007f43cbfcb8b5 in Plasma::ContainmentPrivate::positionPanel () from /usr/lib/libplasma.so.3
#17 0x00007f43cbfcbe0f in Plasma::Containment::resizeEvent () from /usr/lib/libplasma.so.3
#18 0x00007f43c8a12068 in QGraphicsWidget::event () from /usr/lib/libQtGui.so.4
#19 0x00007f43c85334ed in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#20 0x00007f43c853987a in QApplication::notify () from /usr/lib/libQtGui.so.4
#21 0x00007f43caa5a5cb in KApplication::notify () from /usr/lib/libkdeui.so.5
#22 0x00007f43c7e7c401 in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#23 0x00007f43c8a12fba in QGraphicsWidget::setGeometry () from /usr/lib/libQtGui.so.4
#24 0x00007f43c8a10019 in QGraphicsWidget::resize () from /usr/lib/libQtGui.so.4
#25 0x00007f43cc320316 in PanelView::pinchContainment () from /usr/lib/libkdeinit4_plasma.so
#26 0x00007f43cc321209 in PanelView::PanelView () from /usr/lib/libkdeinit4_plasma.so
#27 0x00007f43cc325882 in PlasmaApp::createView () from /usr/lib/libkdeinit4_plasma.so
#28 0x00007f43cc325a61 in PlasmaApp::containmentAdded () from /usr/lib/libkdeinit4_plasma.so
#29 0x00007f43cc327be7 in PlasmaApp::qt_metacall () from /usr/lib/libkdeinit4_plasma.so
#30 0x00007f43c7e8dd30 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#31 0x00007f43cbfd702f in Plasma::Corona::containmentAdded () from /usr/lib/libplasma.so.3
#32 0x00007f43cbfd884b in Plasma::Corona::loadLayout () from /usr/lib/libplasma.so.3
#33 0x00007f43cbfd97f2 in Plasma::Corona::initializeLayout () from /usr/lib/libplasma.so.3
#34 0x00007f43cc324668 in PlasmaApp::corona () from /usr/lib/libkdeinit4_plasma.so
#35 0x00007f43cc3267a5 in PlasmaApp::setupDesktop () from /usr/lib/libkdeinit4_plasma.so
#36 0x00007f43cc327c08 in PlasmaApp::qt_metacall () from /usr/lib/libkdeinit4_plasma.so
#37 0x00007f43c7e8dd30 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#38 0x00007f43c7e9461f in ?? () from /usr/lib/libQtCore.so.4
#39 0x00007f43c7e89cf3 in QObject::event () from /usr/lib/libQtCore.so.4
#40 0x00007f43c85334ed in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#41 0x00007f43c853987a in QApplication::notify () from /usr/lib/libQtGui.so.4
#42 0x00007f43caa5a5cb in KApplication::notify () from /usr/lib/libkdeui.so.5
#43 0x00007f43c7e7c401 in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#44 0x00007f43c7ea3e86 in ?? () from /usr/lib/libQtCore.so.4
#45 0x00007f43c7ea096d in ?? () from /usr/lib/libQtCore.so.4
#46 0x00007f43c421aaa2 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#47 0x00007f43c421e21d in g_main_context_iterate () from /usr/lib/libglib-2.0.so.0
#48 0x00007f43c421e3db in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#49 0x00007f43c7ea08cf in QEventDispatcherGlib::processEvents () from /usr/lib/libQtCore.so.4
#50 0x00007f43c85b404f in ?? () from /usr/lib/libQtGui.so.4
#51 0x00007f43c7e7ad72 in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#52 0x00007f43c7e7af05 in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#53 0x00007f43c7e7d065 in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#54 0x00007f43cc31654b in kdemain () from /usr/lib/libkdeinit4_plasma.so
#55 0x00007f43c7057546 in __libc_start_main () from /lib/libc.so.6
#56 0x0000000000400809 in _start ()