Version:            (using KDE KDE 3.4.2)
Installed from:    Fedora RPMs
OS:                Linux

Backtrace is this:

Using host libthread_db library "/lib/tls/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1208691008 (LWP 4983)]
[KCrash handler]
#4  0xb7f6f402 in ?? ()
#5  0x00a6e7d5 in raise () from /lib/tls/libc.so.6
#6  0x00a70149 in abort () from /lib/tls/libc.so.6
#7  0x002201db in __gnu_cxx::__verbose_terminate_handler ()
   from /usr/lib/libstdc++.so.6
#8  0x0021def1 in __cxa_call_unexpected () from /usr/lib/libstdc++.so.6
#9  0x0021df26 in std::terminate () from /usr/lib/libstdc++.so.6
#10 0x0021e06f in __cxa_throw () from /usr/lib/libstdc++.so.6
#11 0x0021e4bc in operator new () from /usr/lib/libstdc++.so.6
#12 0x0021e559 in operator new[] () from /usr/lib/libstdc++.so.6
#13 0x06d5607e in QString::setLength () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#14 0x06d5e519 in operator>> () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#15 0xb7af68a6 in KlipperWidget::loadHistory ()
   from /usr/lib/kde3/klipper_panelapplet.so
#16 0xb7af75d5 in KlipperWidget::readProperties ()
   from /usr/lib/kde3/klipper_panelapplet.so
#17 0xb7af8ea3 in KlipperWidget::KlipperWidget ()
   from /usr/lib/kde3/klipper_panelapplet.so
#18 0xb7af2d00 in KlipperAppletWidget::KlipperAppletWidget ()
   from /usr/lib/kde3/klipper_panelapplet.so
#19 0xb7af2dfc in KlipperApplet::KlipperApplet ()
   from /usr/lib/kde3/klipper_panelapplet.so
#20 0xb7af2ed0 in init () from /usr/lib/kde3/klipper_panelapplet.so
#21 0x007674ce in PluginManager::loadApplet ()
   from /usr/lib/libkdeinit_kicker.so
#22 0x0075a50c in AppletContainer::AppletContainer ()
   from /usr/lib/libkdeinit_kicker.so
#23 0x00768b42 in PluginManager::createAppletContainer ()
   from /usr/lib/libkdeinit_kicker.so
#24 0x0074fa48 in ContainerArea::loadContainers ()
   from /usr/lib/libkdeinit_kicker.so
#25 0x007508da in ContainerArea::initialize ()
   from /usr/lib/libkdeinit_kicker.so
#26 0x0076e6f2 in PanelExtension::populateContainerArea ()
   from /usr/lib/libkdeinit_kicker.so
#27 0x0076f822 in PanelExtension::qt_invoke ()
   from /usr/lib/libkdeinit_kicker.so
#28 0x06a8d10e in QObject::activate_signal ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#29 0x06dbfbad in QSignal::signal () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#30 0x06aa5eed in QSignal::activate () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#31 0x06aad0ff in QSingleShotTimer::event ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#32 0x06a2e539 in QApplication::internalNotify ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#33 0x06a2e6ca in QApplication::notify ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#34 0x0038a1e8 in KApplication::notify () from /usr/lib/libkdecore.so.4
#35 0x06a228ab in QEventLoop::activateTimers ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#36 0x069de6fe in QEventLoop::processEvents ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#37 0x06a43c8d in QEventLoop::processEvents ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#38 0x06a2d6ea in QApplication::processEvents ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#39 0x06a2d715 in QApplication::processEvents ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#40 0x00763bc0 in ExtensionManager::initialize ()
   from /usr/lib/libkdeinit_kicker.so
#41 0x00764181 in ExtensionManager::qt_invoke ()
   from /usr/lib/libkdeinit_kicker.so
#42 0x06a8d10e in QObject::activate_signal ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#43 0x06dbfbad in QSignal::signal () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#44 0x06aa5eed in QSignal::activate () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#45 0x06aad0ff in QSingleShotTimer::event ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#46 0x06a2e539 in QApplication::internalNotify ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#47 0x06a2e6ca in QApplication::notify ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#48 0x0038a1e8 in KApplication::notify () from /usr/lib/libkdecore.so.4
#49 0x06a228ab in QEventLoop::activateTimers ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#50 0x069de6fe in QEventLoop::processEvents ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#51 0x06a43b85 in QEventLoop::enterLoop ()
   from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#52 0x06a43ade in QEventLoop::exec () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#53 0x06a2d73b in QApplication::exec () from /usr/lib/qt-3.3/lib/libqt-mt.so.3
#54 0x00747518 in kdemain () from /usr/lib/libkdeinit_kicker.so
#55 0x0804861e in ?? ()
#56 0x00000001 in ?? ()
#57 0xbfb6e824 in ?? ()
#58 0x08049704 in ?? ()
#59 0x00b6dff4 in ?? () from /lib/tls/libc.so.6
#60 0x00000000 in ?? ()

When i do login and kde start, kicker crash, and if then i try, from command line, to start it, with 

$ /usr/bin/kicker

it crash.

I don't know very well Linux, i'm italian student!!
Thanks and excuse me for bad english!!