We have already demonstrated how to configure a Smart Host for Internet e-mail using the wizard in Getting Started tasks.
There are situations when you need to change the default port 25 which is used by the Smart Host. For example, your Smart Host provider might require you to use an alternative port like port 587.
Unfortunately, the Wizard does not provide a way to change the default port 25. If you check the Exchange Management Console, you will not find an option to change the Smart Host port too.
In the following screencast, you will see how to change Smart Host port in Small Business Server 2008.