If you guys want, I've been using it, but there's a new version of jmIrc
Just go onto his main page and look for the beta one.
The beta one is for blackberry and it runs well. I can switch apps, it even allows for IRC over Wifi. Since I don't pay for the internet on my phone, it works well. Just wanted to bring that to your attention if for some reason you wanted it immediately. I'm running it on my javeline and it runs quick. Running that With Pandora in the background with 0 lag.
Hey just thought I would let all you guys know I am developing an IRC app for BB, it might require OS4.5 or higher(as thats the api's I'm basing this on) But it will be written specificly for the blackberry and should work much better than jmIrc(jmIrc is the reason I am writing this app, pissed me off one too many times)
Don't expect it like tomorrow, but maybe by the end of the month. BTW I'm slackin from Urban Terror(who happens to own a blackberry.)