Changing the timezone on a server (replace Europe/Amsterdam with your faviorite zone file)

mv /etc/localtime  /etc/localtime-old
cp /usr/share/zoneinfo/Europe/Amsterdam  /etc/localtime

/usr/bin/rdate -s (tick|tock).greyware.com
—or—
/etc/init.d/ntpd stop; ntpdate tick.greyware.com; /etc/init.d/ntpd start

Set the ZONE entry in the file /etc/sysconfig/clock file

vi /etc/sysconfig/clock

Sync the hardware clock

/sbin/hwclock –systohc