I have read the wiki and understand how to set the relay host, user id and user password but I have a question on how to 

identify an alternate port to use for mail relay.

I would add/update the following to the config/config.inc.php file

$config['smtp_server'] = ‘my.host.com:10025’;

$config[‘smtp_user’] = 'userid’;

$config[‘smtp_pass’] = ‘password’;

or is there another 'smtp_port’ parameter or such?

Thanks for the help.

jt