I can talk about using the TCL SMTP and MIME packages (free) for sending mail, or the Direct Adapter (purchased) for sending and receiving mail. I believe there is also another purchased Cloverleaf product that can send and receive mail.
With TCL you can create emails and send them to your exchange server. You are able to add any headers you like, you can send a text body, or html (as an attachment) or any other attachment file. It is up to the receiving mail server to render the content type.
With these TCL packages, you can send mail, not receive it, although I have seen tcl packages that implement an smtp server.
The Direct Adapter is primarily used to send and receive secure email, using the Direct (security) protocol, however, I believe that it can send and receive regular (non-secure) mail as well. To receive mail, it will poll a mailbox on the email server. This product’s strengths are the implementation of the Direct security protocols, and its ease of configuration. This includes tcl access to mail message components, like headers and body. It is very easy to access all headers, to add them and to query them, as they are presented as keyed lists. The Direct Adapter is used as a protocol, like any other Cloverleaf protocol, so the thread using that protocol would represent the email server part of an interface.
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