RFC 822 États:
6.3. RESERVED ADDRESS
It often is necessary to send mail to a site, without know-
ing any of its valid addresses. For example, there may be mail
system dysfunctions, or a user may wish to find out a person's
correct address, at that site.
This standard specifies a single, reserved mailbox address
(local-part) which is to be valid at each site. Mail sent to
that address is to be routed to a person responsible for the
site's mail system or to a person with responsibility for general
site operation. The name of the reserved local-part address is:
Postmaster
so that "Postmaster@domain" is required to be valid.
Note: This reserved local-part must be matched without sensi-
tivity to alphabetic case, so that "POSTMASTER", "postmas-
ter", and even "poStmASteR" is to be accepted.
Également, RFC 5321 États:
4.5.1. Minimum Implementation
[...]
Any system that includes an SMTP server supporting mail relaying or
delivery MUST support the reserved mailbox "postmaster" as a case-
insensitive local name. [...] The requirement to accept mail for
postmaster implies that RCPT commands that specify a mailbox for
postmaster at any of the domains for which the SMTP server provides
mail service, as well as the special case of "RCPT TO:<Postmaster>"
(with no domain specification), MUST be supported.
SMTP systems are expected to make every reasonable effort to accept
mail directed to Postmaster from any other system on the Internet.
Lorsqu'un internaute rencontre un domaine qui ne se comporte pas correctement, peut-il faire quelque chose pour obliger le contrôleur de domaine à appliquer le RFC, en plus de soumettre le domaine à rfc-clueless.org (le remplaçant de rfc-ignorant.org )?