Why is my computers time different when I switch from OS 9 to OS X or vice versa?
Some people have noticed that when booting back and forth between the two Mac OS’s, their system’s time is off. Usually, this happens when the time zones are set different in Mac OS X than in MaCOS 9. To correct this, use the Date and Time control panel in OS 9, and the Date and Time System Preference pane in OS X to set the same time zones.