In this Ignite Realtime video, Daniel Henninger explains how external and internal gateways behave in the context of the IM Gateway Plugin for Openfire.
A big Thank You to Daniel for recording this and sending it in as a community contributed podcast!
The packet filter plugin for Openfire allows you to create rules that will block or reject certain packets to the server. You can get more information and download the plugin from the new Community Plugins space on Ignite Realtime.
Learn more about the plugin from Jive Software's Nate Putnam.