Here is the quote from official Ubuntu website.
Ubuntu announced the release of 5.10 almost 18 months ago, on October 13th. As with the earlier releases, Ubuntu committed to ongoing security and critical fixes for a period of 18 months. The support period is now nearing its end and Ubuntu 5.10 will reach end of life on Friday April 13th 2007. At that time, Ubuntu Security Notices will no longer include information or updated packages for Ubuntu 5.10.It’s kind of sad to see Breezy dying . Breezy was the distribution which made me to switch to Linux.