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[BULK] Re: SORBS contact

On Thu, 28 Jul 2011 14:16:23 PDT, "Brian R. Watters" said:
> Thanks .. their attempts to reach us are blocked via our Barrcacuda's due to
> the fact that they are sending with a blank FROM: and as such Barracuda thinks
> its SPAM 

Please clarify.  Are they sending
MAIL FROM:        (syntactically broken, they need to fix it)
MAIL FROM:<>      totally valid, and if your Barracuda rejects it, it's *your* problem.

And you might want to fix it, since your users will never get a bounce notice
from any RFC-compliant mailer - even if they *wanted* to know that their mail
wasn't delivered.  <> is the RFC-standard way to denote "this mail is a bounce
report or other programmatically generated mail, and if it bounces itself, do *not*
generate another bounce, as that may start a bounce loop".

See RFC5321, sections 3.6, 4.5.5, and 6.1.

(And all those of you anti-spam zealots who want to argue about RFC5321's
SHOULD/MUST pronouncements on the handling of <>, I'll point out that there's
*lots* of wiggle room for those of us with years of SMTP wrangling experience.
On the other hand, we're talking about a potentially misconfigured Barracuda
here, and if a site has a misconfigured Barracuda, urging RFC-compliant
behavior is the only sane choice... ;)

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