Hector Santos wrote:
Otherwise, you risk exposing Bcc: addresses.
I don't see it Ned, and reviewing this is putting a hurting on my brain.
The canonical example I always like to give is:
If the RCPT address is a mailing list, you may not wish to expose that
fact in the To: header. The SMTP server does not have enough information
about the sensitivity of the RCPT argument to know whether or not it's
safe to put it in a header.
But I hope it wasn't misunderstood that we are not talking about a MSA
or MDA doing this. But a post acceptance mail processor, importer, etc,
responsible for storage the direct mail.
See above. The SMTP RCPT argument can be sensitive. And if you mean
adding a To: header after alias expansion, etc. then you are no longer
talking about the x821 RCPT argument.