In case anyone is interested, there is already an example of in-game IRC mod in a game. In this case, Minecraft. If you never cared about the game, you shoulkd notice that the modding in Minecraft is easily the most advanced I've ever seem in a game, and that includes the folks who gave actual graphics to Dwarf Fortress. It blows your mind the complexity some mods bring to the table (to scale, one creates in-game computers and robots, which can be fully coded in Lua (not just a bunch of commands. The actual language), and that's one of the most straightforward ones). Case in point: it has a mod called EiraIRC, which adds a fairly well-featured IRC client to the game. It has plenty of interesting toys, like multiple rooms in one single stream and direct screenshots.
If anyone is interested in trying this out in LT, I suggest checking EiraIRC for inspiration.