"Your msg has been held" messages should come from MAILER-DAEMON

[GoogleCodeExporter]

Right now the moderation notification messages appear to come from list-owner. 
This produces a lot of chatter, especially when spam with bogus sender arrives:

 * Subetha receives spam from [email protected] to mailing list.
 * Subetha sends "your msg has been held" to [email protected].
 * Bogus.com sends back a bounce message to mailing list -owner address.
 * Subetha sends bounce back to owners.

This is bad.  Somehow the "your msg has been held" message must be sent out
without a sender address or with some flag to indicate no response should be
sent.  Precedence: junk?

Original issue reported on code.google.com by [email protected] on 4 Jun 2009 at 10:43