iChat, 2700s and stuff

[Tacitus]

Has anyone any experience of getting videochat working with iChat on a Mac, a 2700 and an AIM account?  In particular which ports get used.  AFAICT it uses 5060, 5297 16384-16403 and possibly 5061, 3478 and 5678.  It also needs 443 to logon to the AIM server.

What seems to happen is that I get an invitation to videochat, accept it and then get the msg 'no response' from the other end.  I can see the other user as being available.  It could be a problem with the firewall at the other end - AIM client running on a Win7 netbook - or it could be that it's accepting on one port and the confirmation comes back on another (blocked) port.  OTOH it could be a problem with the 2700 although if it is I can't see it.

Anyone any ideas?

No hurry since I'll be attacking the Christmas turkey in a while and, no doubt, will be half asleep for the rest of the day.....   

[Rik]

Ah, but which half, Tac?