A Sun machine running Sendmail 8.6 is used as a mailhost to send mail to the Internet in an environment that has MS Mailexchanger or a cc:Mail gateway. Mail from the MS exchange/cc:Mail gateway for the Internet is relayed to the mailhost, which actually delivers the mail. The mail from the Internet is accepted on the mailhost and forwarded to the MS exchanger/cc:mail gateway. The postmaster on the mailhost sees bounced messages with error messages, such as the following:
The original message was received at Thu, 29 May 1997 12:30:41 -0700 from artemis [18.104.22.168] ----- The following addresses had delivery problems ----- <Joe_Smith@cc.test.com> (unrecoverable error) ----- Transcript of session follows ----- ... while talking to cc: >>> MAIL From:<hermes> >>> 501 MAIL FROM: unrecognized address: <hermes> 554 <Joe_Smith@cc.test.com> Remote protocol error
Another situation: The user with cc:Mail sends mail to the Internet, and, due to one of many possible errors (user not found, host not found, and so forth), the message is sent back to the sender (bounces back). When a message is sent back, its recipient`s address is replaced by the sender's address and the sender's address is erased (contains only "<>"). When the bounced sender's address goes through ruleset 3 and then 11 on the user's mail gateway (as it has to return it to the cc:Mail gateway, which is in the local domain => mailer=ether), it is transformed to @@mail-gateway-name.