The following errata for CentOS-2 have been built and uploaded to the centos mirror:

RHEA-2008:0185-05 tzdata enhancement update

Files available:
tzdata-2007k-2.el2_1.noarch.rpm

More details are available from the RedHat web site at
https://rhn.redhat.com/errata/rh21as-errata.html

The easy way to make sure you are up to date with all the latest patches is to run:
# yum update