Thursday, January 9, 2003 07:04 AM
In Internet mail standards, there is now one facility known as DSN's, Delivery Status Notifications, intended for servers to let the sender know that they have received the message and either delivered it or passed it along to the next hop. Actually I think you can request a DSN be returned on SUCCESS, FAILURE, or BOTH; by default, a DSN is returned only on FAILURE. A failure DSN is what you get sometimes, from the "MAILER-DAEMON", "bouncing" a failed message back to the sender.
There is another facility now known as MDN's, Message Disposition Notifications, where the sender adds a header that the recipient's mail client can voluntarily, IF it honors it, ask the receiving user, if they (also voluntarily) wish to respond or not. If they do want to respond, they can either respond affirmatively ("yes the message has been read") or negatively ("No, the message was deleted unread").
Search among Internet RFC's (try http://www.imc.org) for more info about DSN's and MDN's, and search the JavaMail JavaDocs for info on how to request one of them, in your outgoing message.
The DSN request, intended for servers, needs to go into the SMTP envelope, rather than the headers of the message. The MDN request, intended for the recipient, is just a header that you add.