[Users] Message-ID

[Holger Berndt]

On So, 03.02.2013 19:11, Rich Pieri wrote:

>RFC 2822 does not require a single
>properly formatted message-id string in the Message-ID header. There is
>no MUST in the specification. Therefore strict compliance is optional.
>You can put anything you want in the field including multiple ID
>strings.

No. First of all, you may have at most one message-id header (sec 3.6).
This header is a structured header (sec 2.2.2), so a conforming
implementation may NOT "put anything you want" into the header. In
particular, 'The "Message-ID:" field contains a single unique message
identifier.' (sec 3.6.4). How exactly that looks like is defined via
ABNF also in section 3.6.4 - it can't contain multiple ids. And
following these definitions is indeed a MUST for a conforming
implementation (sec 1.3).

>Yes, this blatantly violates the spirit of section 3.6.4. It does not
>violate the letter of that section. My statement stands.

It does violate the wording, and you statement stands ... corrected.

Holger