Message-Id: <199511301940.OAA19789@wilma.cs.utk.edu>
From: Keith Moore <moore@cs.utk.edu>
To: "Kari E. Hurtta" <Kari.Hurtta@dionysos.fmi.fi>
cc: MAILNEWS-L@segate.sunet.se (mailnews-l), drums@cs.utk.edu,
        ratause@dsv.su.se, moore@cs.utk.edu
Subject: Re: On the use of 8-bit transfer 
In-reply-to: Your message of "Thu, 30 Nov 1995 21:24:26 +0200."
             <199511301924.VAA07670@dionysos.fmi.fi> 
Date: Thu, 30 Nov 1995 14:40:40 -0500
Sender: moore@cs.utk.edu

> If 8BITMIME extension is available, it will take care of conversion 
> to 7-bit in event when some MTA does not support 8BITMIME.

Not necessarily.  A server supporting 8BITMIME is not required
to perform such a conversion, though it will often be performed
in practice.

If a SMTP server supporting 8BITMIME finds it is unable to relay
the message over an 8-bit clean path... 
   
   (from RFC 1652)

   A client SMTP has two options in this case: first, it may implement a
   gateway transformation to convert the message into valid 7bit MIME,
   or second, or may treat this as a permanent error and handle it in
   the usual manner for delivery failures.  The specifics of the
   transformation from 8bit MIME to 7bit MIME are not described by this
   RFC; the conversion is nevertheless constrained in the following
   ways:

      (1)  it must cause no loss of information; MIME transport
           encodings must be employed as needed to insure this is
           the case, and

      (2)  the resulting message must be valid 7bit MIME.