Server Edition will continue to receive maintenance updates through June 2011. The list of source packages which will continue to receive security updates for Ubuntu 6.06 LTS Server can be found at http://people.ubuntu.com/~ubuntu-security/dapper/supported.txt for your reference.
The supported upgrade path from Ubuntu 6.06 LTS is via Ubuntu 8.04 LTS. Instructions and caveats for the upgrade may be found at https://help.ubuntu.com/community/HardyUpgrades. For further Ubuntu support,
including commercial support options, see http://www.ubuntu.com/support.
Ubuntu 8.04 LTS continues to be actively supported with security updates and select high-impact bug fixes. All announcements of official security updates for Ubuntu releases are sent to the ubuntu-security-announce mailing list, information about which may be found at https://lists.ubuntu.com/mailman/listinfo/ubuntu-security-announce.
Since its launch in October 2004, Ubuntu has become one of the most highly regarded Linux distributions with millions of users in homes, schools, businesses and governments around the world. Ubuntu is Open
Source software, costs nothing to download, and users are free to customise or alter their software in order to meet their need