Re: message-Id has localhost

[Ken Hornstein]

>Maybe strcmp(hostname,"localhost") should cause that value to be
>ignored, and if necessary, resort to random messageid.  Or maybe that should
>just be the default in some way.

There are a bunch of competing factors here that I am not sure it is
possible to resolve to everyone's satisfaction:

1) Message-IDs must be unique
2) The recommendation for Message-IDs is to use a domain name for the
   right-hand side
3) Most MUAs solve this problem by letting their first-hop MTA generate
   the Message-ID.
4) Some people, for reasons I would classify as "vague", prefer to generate
   their Message-IDs locally so their saved copy of the message has the
   Message-ID in it.
5) Because of (1) and (2), when people configure nmh to generate a
   Message-ID locally the default nmh configuration is to try very
   hard to get the canonical name for the local system (which isn't
   necessarily the same as the user's email domain name, so we can't
   use the value of "localname").
6) As seen in this email thread, that doesn't always work, sometimes because
   of local system configuration for vague reasons.
7) There's not too much prior art here to crib from because of (3).

I'm open to suggestions, but I'm not a fan of special-casing localhost.

--Ken