I have been getting these also.  I get the impression they are
linked to the "Novell GroupWise" system.  I advised them, and the
subscribers involved, to reconfigure as if I continued getting the
"message opened" items I was going to start deleting.  The errors
continued for several days, including "opening" my advisory note, so
I started deleting.
 
So much for volunteer listowners being gentle.
 
Douglas
       Douglas Winship   Hays County, Texas  [log in to unmask]
                    Secondary AUTOCAT Listowner
                              MEDLAB-L