Version:            (using KDE KDE 3.5.5)
Installed from:    Debian testing/unstable Packages
OS:                Linux

I was trying to close the current tab with ctrl-w but mistakenly hit probably first ctrl-q (bound to quit) and then ctrl-w (bound to close tab) (might be vice versa) with a very small delay. Konqueror crashed with the following backtrace:

Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 47463285886240 (LWP 32063)]
[KCrash handler]
#5  0x0000000000000000 in ?? ()
#6  0x00002b2ae52d7507 in qt_inheritedBy () from /usr/lib/libqt-mt.so.3
#7  0x00002b2ae4d0a7e3 in KApplication::notify (this=0x7fffc6d9c490,
    receiver=0x4696630, event=0x7fffc6d9bc90)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kdecore/kapplication.cpp:465
#8  0x00002b2ae5207824 in QApplication::sendSpontaneousEvent ()
   from /usr/lib/libqt-mt.so.3
#9  0x00002b2ae51f911d in QETWidget::translateKeyEvent ()
   from /usr/lib/libqt-mt.so.3
#10 0x00002b2ae5204921 in QApplication::x11ProcessEvent ()
   from /usr/lib/libqt-mt.so.3
#11 0x00002b2ae521a86a in QEventLoop::processEvents ()
   from /usr/lib/libqt-mt.so.3
#12 0x00002b2ae528d79e in QEventLoop::enterLoop () from /usr/lib/libqt-mt.so.3
#13 0x00002b2ae528d5a7 in QEventLoop::exec () from /usr/lib/libqt-mt.so.3
#14 0x00002b2ae5275cf0 in QApplication::exec () from /usr/lib/libqt-mt.so.3
#15 0x00002b2ae8943a9e in kdemain (argc=<value optimized out>,
    argv=<value optimized out>)
    at /build/buildd/kdebase-3.5.5a.dfsg.1/./konqueror/konq_main.cc:206
#16 0x0000000000407566 in launch (argc=2, _name=0x54e778 "konqueror",
    args=0x54e78a "", cwd=0x0, envc=1, envs=0x54e79f "", reset_env=false,
    tty=0x0, avoid_loops=false,
    startup_id_str=0x54e7a8 "lh;1163705172;298937;4987_TIME4064002377")
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kinit/kinit.cpp:673
#17 0x0000000000407eb2 in handle_launcher_request (sock=9)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kinit/kinit.cpp:1240
#18 0x00000000004082b2 in handle_requests (waitForPid=0)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kinit/kinit.cpp:1443
#19 0x00000000004092b3 in main (argc=5, argv=0x7fffc6d9d748,
    envp=0x7fffc6d9d778)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kinit/kinit.cpp:1909
#20 0x00002b2ae44264ca in __libc_start_main () from /lib/libc.so.6
#21 0x0000000000404baa in _start () at ../sysdeps/x86_64/elf/start.S:113