Noel, RFC 2821 section 3.8.4 applies to gateways. My point (2) refers to MTAs acting as a relay.
>From RFC 2821 section 3.7, Relaying... "As discussed in section 2.4.1, a relay SMTP has no need to inspect or act upon the headers or body of the message data and MUST NOT do so except to add its own "Received:" header (section 4.4) and, optionally, to attempt to detect looping in the mail system (see section 6.2)." I was wrong in as much as there is no optional element to this. According to the RFC, a relaying MTA should never act as an Internet Message format cop. It shouldn't even be inspecting the headers, let alone rejecting a message due to their content. The case of fetchmail et al. is interesting. Mail fetched from a POP3 or IMAP server is NOT Internet mail as defined by RFC2821 as POP3 and IMAP are a foreign (non-SMTP) systems. Nor is an MTA configured to fetch mail from a POP3 or IMAP server an SMTP gateway >>> as long as the fetched mail is delivered locally <<<. According to the RFC, the server is acting as a gateway only if it is injecting mail into the internet, that is, delivering remotely over the 'net. One of the modifications I have made to fetchmail is to have the default configuration reject mail not intended for a recipient in a local domain. The original reason for doing this was that mail served by POP3/IMAP servers has arrived on them because they are the local delivery points for the domain(s) being served. Fetchmail is simply acting as a POP3/IMAP client that happens to have some very powerful mail tools at its disposal. They should not be used to deliver the fetched mails anywhere but locally. We now have a second reason for this restriction. Doing otherwise would create an SMTP gateway. There are circumstances when it is impossible to fulfil the rules for a gateway as specified by RFC2821, such as we are unable to correct invalid originator fields. If we can't guarantee to lay by the rules, we shouldn't enter the game. Hopefully this clarifies the responsibilities on James when acting as an SMTP relay and why a fetchmail configuration is not, and should never act as, an SMTP gateway. -- Steve --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
