saltstack/salt — pull request #5214 by faust (2013-05-23 07:47:26+00:00)
Title: Added correct path for Gentoo iptables config file.

Gentoo also have a service to enforce iptables rules, maybe you can consider to handle it in some way.
I would have done that by myself, but this module looks to be still under heavy development and I don't want to create new issues.