Re: header-munging

[Tim Goodwin <[e-mail]>]

> There is also the question of if it is easier to migrate today's
> situation (in which various SMTP servers always modify messages in
> violation of the letter of SMTP) using a new port number or an ESMTP
> keyword.

Does anybody really doubt the answer to this question?  Here's some text
from an earlier message of mine.

  If you are a client that already makes the port number used for SMTP
  configurable, then no code changes are required.  Otherwise, the
  requirement is to make the port number configurable.  All clients which
  might use the SMTP submit port already have a configurable "smarthost";
  by extending the syntax to `mailhost.company.com:25', the port number
  can very easily be made configurable.  10 - 20 lines of code?
  
  In a particular administration which has deployed submit port servers,
  it would be possible to kludge the non-configurable clients to use them;
  either by making the one line change to the source and recompiling, or
  by (horrors) hacking the binary.
  
  On the server side, the major issue is whether the MTA can do both pure
  relaying and submission fixups.  For those that can, both proposals
  are straightforward to implement; for those that can't, both proposals
  will require a similar, possibly large, effort.  However, I claim that
  the SMTP submit port will never be harder to implement than the SUBMIT
  extension.

We are already using the submit port here.  Both of the MTAs we use
(qmail and PP) can easily be configured to support separate submit and
relay ports, with no code changes required.  Two mail clients that we
use (pine and Netscape Navigator) support the `host:port' syntax.

Tim.