Version:           3.5.3 (using KDE 3.5.3 Level "a" , unofficial build of SUSE )
Compiler:          Target: x86_64-suse-linux
OS:                Linux (x86_64) release 2.6.16.27-0.9-default

From "edit event" or "new event" general tab, if Reminder checkbox is unchecked, click on Advanced - opens edit reminders dialog ok. Click on the arrows to change the time, or change from minutes to days, or click on the "before the start" etc selection, Kontact crashes. Totally repeatable. Doesn't happen if the Reminder checkbox is checked, so it's not too upsetting.

Backtrace:
System configuration startup check disabled.

Using host libthread_db library "/lib64/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 47185893752384 (LWP 5327)]
[New Thread 1107310912 (LWP 5331)]
[New Thread 1098918208 (LWP 5330)]
[New Thread 1090525504 (LWP 5329)]
[New Thread 1082132800 (LWP 5328)]
[KCrash handler]
#5  0x00002aaaabc6cb69 in KOEditorAlarms::changed ()
   from /opt/kde3/lib64/libkorganizer.so.1
#6  0x00002aaaabc6d393 in KOEditorAlarms::qt_invoke ()
   from /opt/kde3/lib64/libkorganizer.so.1
#7  0x00002aea4ed1aa8c in QObject::activate_signal ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#8  0x00002aea4ed1b6cf in QObject::activate_signal ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#9  0x00002aea4ee1d112 in QSpinBox::valueChange ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#10 0x00002aea4f01468a in QSpinBox::qt_invoke ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#11 0x00002aea4ed1aa8c in QObject::activate_signal ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#12 0x00002aea4ed1b7a3 in QObject::activate_signal ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#13 0x00002aea4ee1eacf in QSpinWidget::mousePressEvent ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#14 0x00002aea4ed4d986 in QWidget::event ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#15 0x00002aea4ecc3a95 in QApplication::internalNotify ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#16 0x00002aea4ecc48bb in QApplication::notify ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#17 0x00002aea4e6b1b08 in KApplication::notify ()
   from /opt/kde3/lib64/libkdecore.so.4
#18 0x00002aea4ec6c0f4 in QETWidget::translateMouseEvent ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#19 0x00002aea4ec6b2d3 in QApplication::x11ProcessEvent ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#20 0x00002aea4ec7a25f in QEventLoop::processEvents ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#21 0x00002aea4ecd87a1 in QEventLoop::enterLoop ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#22 0x00002aea4ee7a04b in QDialog::exec ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#23 0x00002aaaabc5c8cf in KOEditorGeneral::editAlarms ()
   from /opt/kde3/lib64/libkorganizer.so.1
#24 0x00002aaaabc5c9c8 in KOEditorGeneral::qt_invoke ()
   from /opt/kde3/lib64/libkorganizer.so.1
#25 0x00002aaaabc5ef4d in KOEditorGeneralEvent::qt_invoke ()
   from /opt/kde3/lib64/libkorganizer.so.1
#26 0x00002aea4ed1aa8c in QObject::activate_signal ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#27 0x00002aea4ed1b7a3 in QObject::activate_signal ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#28 0x00002aea4ed4d967 in QWidget::event ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#29 0x00002aea4ecc3a95 in QApplication::internalNotify ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#30 0x00002aea4ecc48bb in QApplication::notify ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#31 0x00002aea4e6b1b08 in KApplication::notify ()
   from /opt/kde3/lib64/libkdecore.so.4
#32 0x00002aea4ec6c0f4 in QETWidget::translateMouseEvent ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#33 0x00002aea4ec6b2d3 in QApplication::x11ProcessEvent ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#34 0x00002aea4ec7a25f in QEventLoop::processEvents ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#35 0x00002aea4ecd87a1 in QEventLoop::enterLoop ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#36 0x00002aea4ecd864a in QEventLoop::exec ()
   from /usr/lib/qt3/lib64/libqt-mt.so.3
#37 0x000000000041537d in main ()