I am doing some research to set up a high volume SMTP relay server for a 
company.  As of right now, they average roughly 4000 7K messages per minute 
during the work day (a total of about 1 million messages per 8 hour work 
day).  By the end of the year, their estimates are to be sending 12 times 
that.  As this is outgoing mail only, local delivery really isnt a big deal, 
we have one incoming server set up for that, and is handling just fine.  

Does anyone have any suggestions for a complete setup for this?  We would 
like to keep the number of servers to a minimum, and the servers would be 
dedicated to SMTP relay, not really running anything else.   We are not 
opposed to running comercial software, right now we use PTMA (from Port25), 
but liceneing for it is $9000 per box, and wouldlike something a bit cheaper. 
 Also, the other obvious problem is bandwith.  Right now I belive we have 2 
T1's set up for this, and I know we will need more down the road.

Any advice would be great.


Jay