One of the departments at my university relies upon Listserv lists for
dozens of the courses they offer. In one set of those courses, each course
has its own separate list. A problem has arisen where an instructor who
has a legitimate need to post the same message to each list periodically
gets marked by Listserv as a spammer. When this happens, Listserv bans him
from posting any further messages for 48 hours, which is very inconvenient.

This is with Listserv 14.5. How can I set up Listserv to allow an
exception to the spam filter mechanism to help out this instructor?