Internally Solaris 10 uses UTC but for programmes that need local timezone information the system timezone is set in the file /etc/default/init (Note: The file /etc/TIMEZONE is a symlink to /etc/default/init).

To set the timezone in /etc/default/init you edit the TZ variable so that, for example:

TZ="Australia/Canberra"

The full list of timezones is in /usr/share/lib/zoneinfo/

After changing the timezone you should restart the system.