[Mimedefang] Domain canonifyin g and RFCs

Ernst du Plooy eduplooy at gmail.com
Thu Oct 20 09:55:25 EDT 2011

I found the (RFC) solution.  According to RFC2821 section 3.6 CNAMES
are allowed like we discussed.  But later in RFC 2821 is states what
should happen when a CNAME is found (section 5).  It states: "The
lookup first attempts to locate an MX record associated with the name.
 If CNAME record is found instead, the resulting name is processed as
if it were the initial name."  So sendmail should rewrite the domain
to the resulting or canonical name.

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