Hey Lance,
Method doesn't have a seperate SMTP gateway, you'll have to set-up an SMTP open relay on your exchange server in order for Method emails to go through. This is something I recommend you speak with your exchange server technicians about, there's usually a structured way to do this -- Microsoft Exchange, for instance, allows you to create "SMTP connectors" which Method can connect with (detailed here: http://support.microsoft.com/kb/265293).
Naeem