Instead of relying on system time zone database, you can use php timezone database which gets updated more frequently. Here is how to do that :

pecl install timezonedb

If you do not have pecl command installed ( For Eg. Centos )  Run the following command :

php /usr/share/php/peclcmd.php install timezonedb

Build process completed successfully Installing '/var/tmp/pear-build-root/install-timezonedb-2007.11//usr/lib/php/modules/' install ok: channel:// You should add "" to php.ini

Add the to php.ini file

Then Reload Apache :

/etc/init.d/httpd reload