23 april 1995 Ottawa Canada
 
Yes, one of the documented features of the unix vacation program is it
will not respond to mail bearing a Precedence: bulk line and certain
other lines.
 
So putting that header line in mail going out over the list will keep
vacation from flooding your list.
 
Good point.
 
Note that if someone writes their own auto-responder program which does
not look for the precedence; bulk line, you will still get mail from
them but most people use vacation to respond to mail when away for a
while.
 
Good luck.
 
Brian Lingard
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