|You click on the iChat AV (2.1) icon. It bounces a couple of times as if it were getting ready to launch and then nothing happens. Does this phenomenon sound familiar? Well, it happened to me a few times and I was at a loss as to what to do. I reinstalled iChat, updated it and even tinkered with the firewall configurations all to no avail.
At my wit's end, I jerked the ethernet cable off and tried launching iChat utterly off-line. Lo and behold, iChat gets launched as it should. Of course it's still off-line. I plug back the ethernet cable and, hey presto, my iChat is good and alive back on-line.
Mind you I do not claim this to be a guaranteed cure-all for all iChat troubles. And yet you might as well give it a try for all its worth and see if this does the trick for you, too.