>We are already using authentication for outgoing mail (SASL), and
>chained certificates. Are these being changed in some way?

What's been added is the capability to configure the PMDF SMTP client
(tcp_smtp_client) to use the SMTP AUTH command (with username and password)
when sending mail out from the PMDF MTA to a remote MTA. This is primarily
needed by home users who are running PMDF on their home systems and have an
ISP that requires a username and password to be able to send out mail
through the ISP's MTA.