i did try to find opensource php + AJAX base IRC client. but found none.
but there is a PEAR library available to connect to IRC server. i will look
into it
and try to write some IRC client. it gonna be fun ;)
Not having read the rest of the thread, I got mildly interested in this and made a simple web based chat thing. You can try it out with seperate browsers (simulating different clients). From what I remember it probably won't cope with the load you're refering to, but it's just an example (oh and (for better or worse) there's no need for an IRC server).
http://www.phpguru.org/chat/chat.php
--
Richard Heyes
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