Unix Change Timezone & Cron Job

To change timzone in unix should set and export TZ variable
TZ=IRST-4:30
format of this variable value depends on platform.

The file /etc/TIMEZONE should be chnaged to reflex settings after reboot.

after changing the timezone cron task should be restarted to apply new timezone information,
/etc/init.d/cron stop
/etc/init.d/cron start

or kill /usr/bin/cron task and start it again.