Version:            (using KDE KDE 3.5.2)
Installed from:    Unlisted Binary Package
Compiler:          gcc 4.0.3 
OS:                Linux

To reproduce: just login to kde and press alt+tab

gdb:
(no debugging symbols found)
Using host libthread_db library "/lib/tls/libthread_db.so.1".
(no debugging symbols found)
`system-supplied DSO at 0xffffe000' has disappeared; keeping its symbols.
(no debugging symbols found)
(no debugging symbols found)
...
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread -1499105600 (LWP 8591)]
(no debugging symbols found)
(no debugging symbols found)
...
(no debugging symbols found)
[KCrash handler]
#6  0xa6938f15 in KWinInternal::Workspace::nextFocusChainClient ()
   from /opt/kde/lib/libkdeinit_kwin.so
#7  0xa6944abb in KWinInternal::TabBox::createClientList ()
   from /opt/kde/lib/libkdeinit_kwin.so
#8  0xa694b0da in KWinInternal::TabBox::reset ()
   from /opt/kde/lib/libkdeinit_kwin.so
#9  0xa694b8e0 in KWinInternal::Workspace::startKDEWalkThroughWindows ()
   from /opt/kde/lib/libkdeinit_kwin.so
#10 0xa696be05 in KWinInternal::Workspace::slotWalkThroughWindows ()
   from /opt/kde/lib/libkdeinit_kwin.so
#11 0xa6981758 in KWinInternal::Workspace::qt_invoke ()
   from /opt/kde/lib/libkdeinit_kwin.so
#12 0xa785153c in KGlobalAccelPrivate::activate ()
   from /opt/kde/lib/libkdecore.so.4
#13 0xa78af85f in KGlobalAccelPrivate::x11KeyPress ()
   from /opt/kde/lib/libkdecore.so.4
#14 0xa78afa9c in KGlobalAccelPrivate::x11Event ()
   from /opt/kde/lib/libkdecore.so.4
#15 0xa78d650f in KApplication::x11EventFilter ()
   from /opt/kde/lib/libkdecore.so.4
#16 0xa697f994 in KWinInternal::Application::x11EventFilter ()
   from /opt/kde/lib/libkdeinit_kwin.so
#17 0xa716f0f5 in qt_set_x11_event_filter () from /opt/qt/lib/libqt-mt.so.3
#18 0xaf9c89c0 in ?? ()
#19 0xaf9c8888 in ?? ()
#20 0x00000001 in ?? ()
#21 0xa7685660 in ?? () from /opt/qt/lib/libqt-mt.so.3
#22 0xa7685660 in ?? () from /opt/qt/lib/libqt-mt.so.3
#23 0x00000017 in ?? ()
#24 0xaf9c8788 in ?? ()
#25 0xa717ae3c in QApplication::x11ProcessEvent ()
   from /opt/qt/lib/libqt-mt.so.3
#26 0xa717ae3c in QApplication::x11ProcessEvent ()
   from /opt/qt/lib/libqt-mt.so.3
#27 0xa718f0ea in QEventLoop::processEvents () from /opt/qt/lib/libqt-mt.so.3
#28 0xa71f81d3 in QEventLoop::enterLoop () from /opt/qt/lib/libqt-mt.so.3
#29 0xa71f80b6 in QEventLoop::exec () from /opt/qt/lib/libqt-mt.so.3
#30 0xa71e10bf in QApplication::exec () from /opt/qt/lib/libqt-mt.so.3
#31 0xa697c6cd in kdemain () from /opt/kde/lib/libkdeinit_kwin.so
#32 0xa774b674 in kdeinitmain () from /opt/kde/lib/kde3/kwin.so
#33 0x0804dc46 in ?? ()
#34 0x00000001 in ?? ()
#35 0x08082500 in ?? ()
#36 0x00000001 in ?? ()
#37 0x00000000 in ?? ()