Subject: [EAI] More comments on draft-ietf-eai-rfc5336bis-00

From: Ernie Dainow <[email-masked]>
Date: Thu, 08 Jul 2010 15:51:41 -0400

Expanding on an earlier comment by SM, RFC2821 has been obsoleted by 
RFC5321.
So all references in the document to [RFC2821] should be changed to 
[RFC5321].
Similarly all references to [RFC2822 ] should be changed to [RFC5322].

3.2. The UTF8SMTPbis Extension
(last paragraph)  

   If a server advertises UTF8SMTP and the client does not recognize the
   extension, the client may send a regular message [RFC2821 <http://tools.ietf.org/html/rfc2821>] and
   [RFC2822 <http://tools.ietf.org/html/rfc2822>].  In this case, the client may continue to use the
   [RFC3490 <http://tools.ietf.org/html/rfc3490>] or [RFC5890 <http://tools.ietf.org/html/rfc5890>] ToAscii() to encode the domain portion of an
   address.

The second sentence is not very clear. Is the following what is meant?

    In this case, the client will not be able to transmit any messages
    which contain non-ASCII characters in the local-part of any email
    addresses. If the non-ASCII characters are confined only to the
    domain portion of the address, such a client will be able to
    transmit messages if it uses [RFC3490] or [RFC5890] ToAscii() to
    encode the domain portions of these addresses.

(last sentence)

   UTF8SMTP servers MUST recognize and decode the ACE label(s)
   as appropriate.

A final delivery MTA must recognize that a domain containing UTF8 
characters is equivalent to an ACE of that domain, but it's not clear 
where a server would actually need to decode an ACE back to UTF8. Can an 
example be provided? If not, omit this sentence.

3.6.2. Mail eXchangers

   Authorized servers
   are generally listed in MX records as described in RFC 2821 <http://tools.ietf.org/html/rfc2821>.  When
   more than one server accepts mail for the domain-part of a mailbox,
   it is strongly advised that either all or none of them support the
   UTF8SMTPbis extension.  Otherwise, surprising downgrades can happen
   during temporary failures, which users might perceive as a serious
   reliability issue.

We don't have downgrade anymore. Shouldn't the last sentence read

    Otherwise, delivery failures will occur for some internationalized
    messages and not for others, depending on which MX record is selected.

-Ernie