[Ti] is iChat different from Yahoo Messenger, MSN etc?

[Mike Bigley]

>well, the ports used by iChat will probably be blocked. it might not 
>even be the port ranges necessary for instant messeging, but for 
>video conferencing ... iChat uses the most port ranges out of the 
>instant messenger services i know ....

This could be a clue; I have been investigating Belize and their 
telecom is government owned and is blocking all VOIP because they 
don't want to keep their monopoly on telecom services.  This could be 
similar in your situation, as iChat's voice and video services may 
use such protocols.