< messaging , protocol > ("Extended TURN ") An ESMTP command (first defined in RFC 1985 ) with which a client asks the server to deliver queued mail to the client via a new ESMTP connection.
ETRN supersedes the SMTP "TURN" command in the same way that ESMTP's " EHLO " supersedes SMTP's " HELO ".
(1997-11-21)