Hello, a friend (under Tiger) has this issue when he tries to talk with his dad (under Panther), since I have no mic to give it a try I would like if anyone here know about this iChat issue. It worked under Panther (both computers with Panther).
I have searched here for similar topics, hey I am not a newbie

and found some references to
open some firewall ports , I guess my friend must open those ports included
here
But being honest I unknow if he is using the built-in Mac OS X firewall.
Thanks.