> (1) All subscribers need to be set to NOPOST,DIGEST except for the list
> managers themselves.  No subscribers should be able to reset the DIGEST
> option.  I.E., I need a method to lock down subscription options.

Use email addresses on the list that are equivalent to, but different
in form from the subscriber's real email address.  This will prevent
most people from changing options via email.  Someone who knows the
form of address being used could change options through the web
interface, but you could minimize that by making the list Review=Owner.
Or you could make the list Confidential=Yes, thus keeping it out of the
web interface.

Example address:  [log in to unmask]