Ichat And Bt


I have recently starting using the iChat with the iSight and have BT broadband with the Voyager 205 ADSL router connected wirelessly with an apple airport express. I am using a .mac account for iChat. I have a G5 with Mac OS X Version 10.4.2 and iChat AV 3.0.1 (v392).

I am having trouble connecting with people. I can initiate an AV chat with my brother in New York, but if he invites me I cannot accept and get "connection failed because XX did not respond". He has a .mac account.

Also my father has an AIM account and he is greyed out all the time. They say that they can see that I am online and we can have a text chat but I cannot initiate a chat with him and have the same problem as the one that I have with my brother when he invites me to have an AV chat.

I have tried the apple helpline but they do not seem to be able to offer any help and suggested that I contact BT as they say it is not a problem with my computer.

What can I do?