Colloquy is an IRC mail client for Mac that will allow you to chat with your loved ones at any time. Colloquy offers to make DCC file transfers, contains a list of contacts, offers support for emoticons. With an interface that you can customize, this software includes several features including a dictionary that allows you to script, a file transfer tool through DCC called File Transfer Medly. It is also possible to resume downloads, you also have several emoticons available to you.
Client SILC, ICB, IRC
Colloquy is also a SILC client, ICB for Mac, it has a SILC toolbox, is compatible with plugins, it supports Apple Script, it is secure with SSL, it is possible to customize the exchanges with WebKit, it allows discussions on multiple windows, tabs, a collapsible side panel. In addition you can access a chat on different servers simultaneously.
In short you can discover the other features of Colloquy by testing it on your Mac while noting that its configuration requires a Mac OS 10.4.