CentOS Errata and Security Advisory CESA-2011:1240:
This is the 6-month notification for the End of Life for the CentOS 4 distribution. The upstream provider will discontinue public updates of their EL4 product on February 29th, 2012. The CentOS Project will end support for CentOS 4 on the same date.
CentOS 4, as well as all previously released versions of CentOS, will continue to be available in the Centos Vault:
This CESA includes a new centos-release file that reminds you of the February 29th, 2012 end of life date.
Users still running production workloads on CentOS 4 are advised to begin planning the upgrade to CentOS 5 or CentOS 6 before the EOL date.
For users who are unable to migrate off the EL 4 code base before its end-of-life date, the upstream provider intends to offer a limited, optional extension program. The CentOS Project recommends that you contact their sales team for a price quote for their extended service if you can not move to a newer code base before February 29th, 2012.