Debian版mozアプリの旧安定版バックポート打ち切り
http://lists.debian.org/debian-security-announce/2013/msg00107.html

We don't have the resources to backport security fixes to the Iceweasel release in oldstable-security any longer.
If you're up to the task and want to help, please get in touch with [email protected].
Otherwise, we'll announce the end of security support for Iceweasel, Icedove and Iceape in Squeeze in the next update round.