https://private.yoda.pw/i/001559.png

That's ^O, used for resetting formating and color back to defaults, it should probably translated to §r in minecraft. There are also ^B for bold, ^U for underline, ^R for reverse (fore- and background swapped) and ^I for italics. You can look up the corresponding codes in Minecraft on http://minecraft.gamepedia.com/Formatting_Codes .

Translating colors is bugged right now. From MC to IRC the § are simply dropped resulting in messages like "<cNickr> Hello". IRC to MC works, except if someone uses black (^C1) and a 2-digit color in the same line, the replaceAll in util/Util.java line 342 causes all further 2-digit colors to be replaced with §0<second digit>, resulting in black text plus that extra digit instead of the intended color.

Edit: escaped brackets

Good to see someone finally making use of EiraIRC's open-source-ness ;)

Thanks for the information, will probably spare me some research when I get to it.