How do I change the default port away from 80 on a Mac for Messanger?

I am unable to receive files and someone said that if my ISP blocks port 80 that I need to change the default port. Does anyone know how to do this?How do I change the default port away from 80 on a Mac for Messanger?
In the Preferences for Yahoo! Messenger, click on the connection tab, and then choose Behind Firewall. That usually solves these problems. If this doesn't work for you, try another chat client, such as Adium (http://www.adiumx.com/) and there are specific settings to change what port you're using for that service.How do I change the default port away from 80 on a Mac for Messanger?
Are you talking about iChat? If so, here's how to change the TCP port settings from 80 back to the default. Make sure you're logged out before you try this.



1. Browse to: iChat %26gt; Preferences

2. Click %26quot;Accounts%26quot;

3. Click %26quot;Server Settings%26quot;

4. Change the port number to 5190 or just click %26quot;use default settings.%26quot;