Can the Web Interface be forced to accept user@myhost format as a
signon?

Its insistant that web users create [log in to unmask] format,
 but ive got hundreds of list members and some owners in the Non FQDN
 format already. Last hurdle on this migration is now web management and
 access.

The @myhost system is already a working LOCAL var, so mail/lists work
 already...