[EAI] Re: MTA -> Final delievery MTA -> MDA

[Frank Ellermann <nobody at xyzzy.claranet.de>]

Kari Hurtta wrote:
 
> Lets look one possibility when downgrade fails.

Thanks for the example, I didn't know that LMTP behind ESMTP
works (or can work) "within" the SMTP session, a bit like a
"call forward verification", but here in your example after
DATA.

[...]
>      F <- D        XYZ <boss at example.com> UTF8SMTP not accepted
[...]
>      F -> D        QUIT
>      F <- D        221 mail.example.com closing connection
> C <- F             ABC UTf8SMTP downgrade fails for some recipients
> C -> F             MAIL FROM:<support at example.org> BODY=7BIT SIZE=323
> C <- F             250 Ok.
> C -> F             RCPT TO:<client at example.com>
> C <- F             250 Ok.
  C -> F             DATA           
> C <- F             354 Start mail input; end with <CRLF>.<CRLF>
[...2nd attempt for client@ ...]
> C -> F             Your case #XCVXBX is closed.
> C -> F             .
> C <- F             250 Message already delivered
> C -> F             MAIL FROM:<support at example.org> BODY=7BIT SIZE=323
> C <- F             250 Ok.
> C -> F             RCPT TO:<boss at example.com>
[...3rd attempt for boss@, client doesn't try to be smart, good...]
> C <- F             XYZ UTF8SMTP downgrade fails
> C -> F             QUIT
> C <- F             221 mail.example.com closing connection
 
> So actually it is very usefull that there is HDR=UTF8SMTP
> parameter on LMTP MAIL FROM.

Sorry, I know very near to nothing about LMTP, I can't judge
it.  If you think that HDR=UTF8SMTP helps with LMTP even if
it's not adopted by the UTF8SMTP folks here, go for it.

Frank



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