My wife recently tried iChatting from our Tiger-based macbook with her mother (who was in an Apple store class at that moment) - her mother was using Leopard on a newer Macbook. My wife got the message saying "mom wants to chat", to which she accepted. But then it said something along the lines of "IP address is not valid" and wouldn't work. Now, I've found a really long-winded article on Apple about opening all kind of ports on both sides, NAT routers, etc.. Why is it this complicated? Skype works fine w/ this computer when I chat w/ *my* parents but my wife's mom wants to use ichat. Is there something about iChat that doesn't "just work"? Do I need to go into my router and set up port rules and go into my mac's command line and edit ipfw rules? I'm not a unix guy. Or was this more likely an issue at the Apple store on my mother-in-law's side?