Version:            (using KDE KDE 3.5.6)
Installed from:    Ubuntu Packages
OS:                Linux

I have no idea on how to trigger this crash, but it is happening too often now (once a day).
Usually the crash happens when trying to open a window.
This is the back trace report.

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Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
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[Thread debugging using libthread_db enabled]
[New Thread -1233004320 (LWP 7063)]
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[KCrash handler]
#6  0xb677d4c0 in KWinInternal::Workspace::updateMinimizedOfTransients (
    this=0x80ba410, c=0x8194828)
    at /build/buildd/kdebase-3.5.6/./kwin/group.cpp:387
#7  0xb677d5aa in KWinInternal::Client::unminimize (this=0x8194828,
    avoid_animation=true) at /build/buildd/kdebase-3.5.6/./kwin/client.cpp:630
#8  0xb677db43 in KWinInternal::Workspace::resetShowingDesktop (
    this=0x80ba410, keep_hidden=false)
    at /build/buildd/kdebase-3.5.6/./kwin/workspace.cpp:2730
#9  0xb678a4e3 in KWinInternal::Client::manage (this=0x819a9d8, w=67108871,
    isMapped=false) at /build/buildd/kdebase-3.5.6/./kwin/manage.cpp:471
#10 0xb678a896 in KWinInternal::Workspace::createClient (this=0x80ba410,
    w=67108871, is_mapped=false)
    at /build/buildd/kdebase-3.5.6/./kwin/workspace.cpp:484
#11 0xb678e137 in KWinInternal::Workspace::workspaceEvent (this=0x80ba410,
    e=0xbfe82ab8) at /build/buildd/kdebase-3.5.6/./kwin/events.cpp:360
#12 0xb678e22e in KWinInternal::Application::x11EventFilter (this=0xbfe82c98,
    e=0xbfe82ab8) at /build/buildd/kdebase-3.5.6/./kwin/main.cpp:155
#13 0xb7138133 in ?? () from /usr/lib/libqt-mt.so.3
#14 0xbfe82c98 in ?? ()
#15 0xbfe82ab8 in ?? ()
#16 0x00100000 in ?? ()
#17 0xb76eaab0 in ?? () from /usr/lib/libqt-mt.so.3
#18 0xbfe82ab8 in ?? ()
#19 0xb76eaab0 in ?? () from /usr/lib/libqt-mt.so.3
#20 0xbfe82958 in ?? ()
#21 0xb71488c2 in QApplication::x11ProcessEvent () from /usr/lib/libqt-mt.so.3
Backtrace stopped: frame did not save the PC
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