The Server Admin tool in servermgr_ipfilter for Mac OS X 10.4 to 10.4.2, when using multiple subnets and Address Groups, does not always properly write firewall rules to the Active Rules when certain conditions occur, which could result in firewall policies that are less restrictive than intended by the administrator.
http://securitytracker.com/id?1014708
http://lists.apple.com/archives/security-announce/2005/Aug/msg00000.html
http://lists.apple.com/archives/security-announce/2005//Aug/msg00001.html