After re-read rfc2821 I find this : 4.2.5 Reply Codes After DATA and the Subsequent <CRLF>.<CRLF>
.... snip to last paragraph When an SMTP server returns a permanent error status (5yz) code after the DATA command is completely with <CRLF>.<CRLF>, it MUST NOT make any subsequent attempt to deliver the message. As with temporary error status codes, the SMTP client retains responsibility for the message, but SHOULD not again attempt delivery to the same server without user review and intervention of the message. It seems that the smtp client (xmail here when sending to smtp gateways or mx servers), when receiving a 5xx code SHOULD NOT again attempt to the same server. So Davide is right, xmail can try the other gateways/mx available in the list. But with the possible case (Oliver case here) that "all the gateways/mxs return a 5xx error" the smtp client have no more options to send the mail (because it "SHOULD not again attempt delivery to the same server"). So the smtp client (xmail here) have to send an ndr to ask/alert the sender what to do next (to comply with "without user review and intervention of the message") :) Francis - To unsubscribe from this list: send the line "unsubscribe xmail" in the body of a message to [EMAIL PROTECTED] For general help: send the line "help" in the body of a message to [EMAIL PROTECTED]
