mail filter sender

[freshorange]

How do I configure cpanel that it sends mail to the outside world only from a restricted list of our local users?
example:
user1 only can send email to cpaneldomain.com but he can't send email to yahoo, gmail, hotmail, and etc.
but
user2 can send email to all domain destionation.

need your advice

thanks

[thewebhosting]

It is not possible to block to send email for a particular email account. It will be done to all the email account of the domain.