Use Smarthost with Exchange 2003

1. Open Exchange System Manager
2. Select [ServerName], click Protocols, and then click SMTP.
3. Right-click the Default SMTP Virtual Server object, and click Properties.


4. Click the Delivery tab

5. Click Advanced

6. Inset the hostname off the smarthost/relay server


Change Outbound Port:
1. Click Outbound connections

2. Change TCP port to 26

 

Change smtp Receive port Exchange 2003

Here is how you change det Listening port on Exchange 2003

Change Receive Port:
1. Open Exchange System Manager
2. Select [ServerName], click Protocols, and then click SMTP.
3. Right-click the Default SMTP Virtual Server object, and click Properties.
4. On the General tab, click the Advanced button, click the Edit button.

5. Change the port number to port 26

Source: http://support.microsoft.com/kb/274842