Warning: this can make a message destined for multiple recipients to bypass maia for all recipients, which could let a virus leak through to another protected account. If anyone has a better solution, please help!

One simple solution provided on the mailing list for postfix users:

smtpd_recipient_restrictions = check_recipient_access hash:/etc/postfix/bypass

/etc/postfix/bypass

username@domain.org FILTER smtp:[127.0.0.1]:10025