That's one of the best ideas I've heard since a long time!
I think this will make the task of the translators a lot easier and more fun!
Now find a good name... "Online Messenger Plus! Translator" is a bit long, can you abbreviate it? If you find 2 words to put in front of it which start with a P and an R, you can have "PROMPT".
* Matti approves! (although his vote is worth nothing as he's not a translator whatsoever...)