um... before we jump to conclusions and say that it makes sense and therefore should be done, let\'s look at the situation in the game. There are 8+ races of humaniods living in one city for many (possibly) many generations. There is a lot of interbreeding between them. I think all that would be left of original languages, if they had them (apparently they had little trouble communicating when they first interacted) would be accents or dialects, which could be programmed into the language that the npc\'s use, and could then be picked up by the characters, if they wished so. If you want to roleplay, you may want to use these dialects or make codes that only your guild knows, like a thief\'s cant or such. As with such dialects (such as cockney in our world) it is very hard to understand.
Unfortunately, accents are a whole lot easier to decipher when written down than if it were just spoken, so it may be used mostly for roleplaying and not for giving secret messages.
I\'m sorry if this post is badly put together. Concussion I head have in.