The IRC is #bsdcert on freenode.

A quick tutorial on using GAIM for IRC is at <http://www.kplug.org/ircchatsetup/gaim-irc/index.html>.
(For the server I used "irc.freenode.net".
Be sure to use #bsdcert as the channel.
It might also be useful to Enable Logging under the Options menu.)

Some more examples for various clients are at <http://gc.stonewallcs.com/IRC/clients/>.