On Tue, 8 Aug 1995 10:17:44 EDT you said: ><blush> I have a would-be subscriber sending from a site that adds a >"Sender: postmaster@......" header to every message in addition to >the user's "From:" My initial " don't do that !!!" resulted in a >quote from RFC822 ( sec 4.4 -> 4.4.4 ) ( definitions of FROM/SENDER ) >The original reject from LISTSERV follows - How SHOULD I advise this >user ??? - mike This "gratuitous senderization" is certainly NOT the norm. I can quote from RFC822 too (see below) and say that I really doubt the postmaster is personally sending this message for the person. In addition, since the Sender: address is a key place for errors to be sent the postmaster is depriving the user of error messages by doing this. It seems to me that EVERY message from that system is probably sent the same way which would seem to make the Sender: field redundant and it should not be used. In other words, RFC 822 seems to be pretty clear that Sender is to be used for special cases. The correct use of Sender: is the way it is used by MLM's like LISTSERV - to indicate that the mail, while it may have a user's From: adress, is being sent by a list. 4.4.2. SENDER / RESENT-SENDER This field contains the authenticated identity of the AGENT (person, system or process) that sends the message. It is intended for use when the sender is not the author of the mes- sage, or to indicate who among a group of authors actually sent the message. If the contents of the "Sender" field would be completely redundant with the "From" field, then the "Sender" field need not be present and its use is discouraged (though still legal). In particular, the "Sender" field MUST be present if it is NOT the same as the "From" Field. Marty Disclaimer: Obviously, these are just my opinions...