I fully agree with Harry Williams on this.  The existing standards just
DO NOT cut it.  A NEW standard to augment what we have now is an absolute
MUST!!!
 
This standard MUST be as much a standard as any other existing standard
so that we will have SOMETHING to "wave in people's faces" when it breaks
again (and it WILL many more times before we are done).
 
Suggestions like:  REJECT-TO: and ERROR-TO: are quite good.
 
I would also suggest an additional field DEDICATED to an error NUMBER that
describes WHY the mail was returned.  It could be like:
 
>>>     ERROR-IS: 301 addressed userid does not exist
 
If the standard includes this, it must define the numbers.
 
I would urge that such a standard also specify that at least the original
headers, modified to not be part of the headers of the return mail, be
included for diagnostice purposes.  Some mailers do not do this.
 
Finally, such a standard should take into consideration the impact of
mailing lists OTHER THAN LISTSERV, especially those on ARPANET.