restricting persona's via smtp?

[Vladimir]

Zimbra has this nice persona model where users can only choose from a list of preconfigure addresses for their persona's. However if a user set their thunderbird connection to pretend they are someone else, smtp auth logs aside, the MTA happily lets them use that "from" address basically allowing the user to use any "persona" they want.

Anyone know of a way to restrict this to the list of addresses configured for the user?

[iway]

You could disable the preference "Allow sending from any address" in the Admin UI.

[Vladimir]

Yes, but that only solves the problem via the web client. Someone using imap/smtp is not restricted by that, which is the problem I'm refering to.