For your convience, here is a list of Instant Messaging (IM) clients that are known to support IRC.

Centericq

Centericq is a text mode menu- and window-driven instant messaging interface that supports the ICQ, Yahoo!, AIM, MSN, IRC, Jabber, LiveJournal, and Gadu-Gadu protocols. It allows you to send, receive, and forward messages, URLs, SMSes (both through the ICQ server and email gateways supported by Mirabilis), contacts, and email express messages, and it has many other useful features. Known to work in Linux, FreeBSD, NetBSD, OpenBSD, Solaris, Windows and Mac OS X/Darwin Operating Systems.