you can probly make you own timezone patch.
a number of unix versions have a official patch but you can often roll your own.....
source files can be found on the internet at
Sources for Time Zone and Daylight Saving Time Data
you will need to find your timezone source files.
try /usr/share/lib/zoneinfo/src/
once you have found the location then update the timezone file for the zone your in and then run it through zic, and reboot system
# zic /usr/share/lib/zoneinfo/src/<zonefile of choice>
# reboot