It's working for me for the local part. As I am at work I can not test the internet part.
The main problem for me is that you send a message even when it is an empty one, and that à,ë,ï,é,è... are not supported.
EDIT: Even ê,ô,û,â and others are not.
Hmm ha, and the just the server is consumming 27% of my Athlon64 X2 .
For the internet thing, I can say that you will not have any other problem than a bigger latency. As a chat is not necessary a time critical app, you do not need to worry.