Version:           1.9.1 (using KDE 3.5.0 Level "a" , SUSE 9.2 UNSUPPORTED)
Compiler:          gcc version 3.3.4 (pre 3.3.5 20040809)
OS:                Linux (i686) release 2.6.8-24.19-default

I was composing a message in English and wanted to do a spell check. The language however was still Dutch. I changed to English and after that Kontact/Kmail crashed. After starting up Kontact both Kontact and the composer with the message I was composing appeared and the language was now set to English. I would expect no crash after the change of language in the spell check.
I did have this behaviour before, so it seems to be reproducible.

The traceback is:
Using host libthread_db library "/lib/tls/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 1106002080 (LWP 5026)]
[New Thread 1140833200 (LWP 10836)]
[Thread debugging using libthread_db enabled]
[New Thread 1106002080 (LWP 5026)]
[New Thread 1140833200 (LWP 10836)]
[Thread debugging using libthread_db enabled]
[New Thread 1106002080 (LWP 5026)]
[New Thread 1140833200 (LWP 10836)]
[New Thread 1128393648 (LWP 5036)]
[New Thread 1126292400 (LWP 5035)]
[New Thread 1124191152 (LWP 5034)]
[New Thread 1122089904 (LWP 5033)]
[KCrash handler]
#7  0x41127ffa in QObject::activate_signal ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#8  0x41484983 in QComboBox::activated () from /usr/lib/qt3/lib/libqt-mt.so.3
#9  0x411ca451 in QComboBox::internalActivate ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#10 0x414847f5 in QComboBox::qt_invoke () from /usr/lib/qt3/lib/libqt-mt.so.3
#11 0x41127d6e in QObject::activate_signal ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#12 0x4112839d in QObject::activate_signal ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#13 0x4148d8e1 in QListBox::selected () from /usr/lib/qt3/lib/libqt-mt.so.3
#14 0x41205123 in QListBox::mouseDoubleClickEvent ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#15 0x4115e1d4 in QWidget::event () from /usr/lib/qt3/lib/libqt-mt.so.3
#16 0x410c502f in QApplication::internalNotify ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#17 0x410c73d6 in QApplication::notify () from /usr/lib/qt3/lib/libqt-mt.so.3
#18 0x40dd5911 in KApplication::notify () from /opt/kde3/lib/libkdecore.so.4
#19 0x411c7c53 in QComboBox::eventFilter ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#20 0x4112860e in QObject::activate_filters ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#21 0x411286f0 in QObject::event () from /usr/lib/qt3/lib/libqt-mt.so.3
#22 0x4115dcbf in QWidget::event () from /usr/lib/qt3/lib/libqt-mt.so.3
#23 0x410c502f in QApplication::internalNotify ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#24 0x410c73d6 in QApplication::notify () from /usr/lib/qt3/lib/libqt-mt.so.3
#25 0x40dd5911 in KApplication::notify () from /opt/kde3/lib/libkdecore.so.4
#26 0x410625f9 in QETWidget::translateMouseEvent ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#27 0x41061276 in QApplication::x11ProcessEvent ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#28 0x41071e48 in QEventLoop::processEvents ()
   from /usr/lib/qt3/lib/libqt-mt.so.3
#29 0x410dcfc1 in QEventLoop::enterLoop () from /usr/lib/qt3/lib/libqt-mt.so.3
#30 0x410dce06 in QEventLoop::exec () from /usr/lib/qt3/lib/libqt-mt.so.3
#31 0x410c6abf in QApplication::exec () from /usr/lib/qt3/lib/libqt-mt.so.3
#32 0x08064345 in main ()