I feel like a foreigner in this forum ;)

We have a few Apple Mac G4's at work, running OS 9.x  
I've tried to search Apple's site, but been unsuccessful in finding anything related to this OS and the daylight savings time changes in September.

I'm not very Apple literate..  Does anyone know of how I can change the 'Wellington, NZ'  timezone file so the new dates are incorporated?  I can't find anything (unless I've missed it) that will allow this on the Mac.  I need to be able to change the start date/start time - end date/end time.

The times need to be able to be changed, as I've noticed Microsoft on the PC timezone files at least, has the wrong
time (2am) for when the clocks go back.. It should be 3am officially back to 2am.  The MAC may be the same.

Can anyone point me in the right direction to find a patch for OS 9.x or a utility for the Mac to change the timezone file?

(a stranger in a strange land!) ;)