IRClib is pure Java 1.2 IRC implementation. The IRClib library is designed very cleanly, supports RFC1459 and supports SSL connections. moepII is a Java IRC client program.
AOLibrary is a java-based library for writing chat bots that can be used with the game Anarchy Online. (Bots are often used to facilitate communications within an in-game organization or guild.) The library is written in Java 6.