PJirc's interface is MUCH nicer, it's FREE and it comes with source code so it could be modified to update "who's online".
It also solves the problem of duplicate nicknames. If a nickname is already in use you can have it automatically append a random number to the end of the nickname to make it unique.
The primary reason I first looked at it is it can be called from anywhere, the license doesn't lock it down to one domain, so you could set up a chat portal for other sites.
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