In the REFCARD docs for 1.7b, I found the following:
 
CONFIRM      listname1 <listname2 <...>>>      Confirm your subscription
                                               (when LISTSERV requests it)
 
Grepping for 'CONFIRM' doesn't show anything about it in any of the
other LISTSERV docs I've found.
 
Does anyone know if/how I can initiate a confirmation/expiration
sequence (asking all members for confirmation, expiring those that
don't), if I am the list owner?  What usually initiates it?  Do you
know where I can find docs for this?
 
Steve