[Mimedefang] Received headers in general

[Les Mikesell]

On Tue, May 22, 2012 at 7:41 PM,  <kd6lvw at yahoo.com> wrote:
>
>
> Exchange and gmail claim SMTP transport but fail to follow the required syntax.

Exchange isn't natively SMTP, so that mail doesn't originate in an
SMTP environment.   And if you want to claim to know more about
internet mail that google well, good luck with that.

> RFC 5321 does not ban rejecting on that basis.  It bans only the application of SMTP syntax to non-SMTP headers.

New requirements rarely/never mandate that you stop interoperating
with existing behavior.   As far as I know, the only time the whole
internet was required to change something at the same time was Jan 1,
1983 when TCP/IP was standardized.   Even if you wanted to believe
that there was a mandate to reject, which there isn't, you would have
to give the senders time to adapt to new requirements.  A long time.

> Where "MUST" is given, such means that there is something to enforce.

That's not what MUST means.  It applies to what _you_ generate.

> I enforce it and get much less spam as a result.

Well, no.  Your own numbers did not show it as being an indicator of spam.

-- 
   Les Mikesell
     lesmikesell at gmail.com