Have a search of the forums, there were instructions posted around the beginning of the year that may help you. You can either use the forum interface to log in, in which case you need to have java loaded. Or, you can use a dedicated IRC program.
Cannot hep you with your specific problem, but chat was working ok last night.
ok- chat problems - sometimes when i conect to chat the jave window comes up and i have to click yes -if i click No accidently then i cant conect.
I then have to close all explorer windows - empty the IE cache, temp internet files and cookies then start again.