Mac OS X 10.2.8 or Earlier: Menu Bar Clock Unexpectedly Uses 24-Hour Setting
The clock in the menu bar may unexpectedly use a 24-hour setting instead of a 12-hour clock. Use the International preference pane to change the clock's setting.
Symptom
The clock in the menu bar may unexpectedly use a 24-hour setting instead of a 12-hour clock.
An inaccurate "AM" or "PM" may appear.
This document will be updated as more information becomes available.