Re: [exim] exim still accepting email after 550 from acl_che…

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Author: Mike Brudenell
Date:  
To: Patrick von der Hagen
CC: Exim Users
Subject: Re: [exim] exim still accepting email after 550 from acl_check_helo
On 12 January 2016 at 16:36, Patrick von der Hagen <patrick.hagen@???>
wrote:

> The way I reed it: "the client MUST issue HELO or EHLO, but it SHOULD
> send EHLO instead of HELO."
>


Nope, I disagree with the above. The RFC says:



1. A client SMTP SHOULD start an SMTP session by issuing the EHLO
command.
2. Older client SMTP systems MAY, as discussed above, use HELO (as
specified in RFC 821) instead of EHLO …
3. In any event, a client MUST issue HELO or EHLO before starting a mail
transaction.

As far as I can see there is nothing which says "the client MUST issue HELO
or EHLO" apart from in the context of starting a mail transaction.
(Otherwise you wouldn't be able to issue a QUIT without first sending a
EHLO/HELO! :-)


> There is no need for non-mail transactions instructions...
>


Cheers,
Mike B-)

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