TMDA Mail Gateway

Hi all

I'd like to use TMDA as a Mail Gateway for an exchange server.

Is that possible? I thougth about putting a machine with TMDA before the
Exchange and create the same accounts, and change the release-pending
messages to send the message to exchange's smtp instead of putting it in
users mailbox.

Does any one tried that? There's any other ways?

thanks alot
thiago lima.