Procmail filters for outgoing mail

I installed a procmail 3.22 service on RH7.2 - Sendmail. And, I could do some 
coming mail filters (recipes). But I couldn't use these kind of filters 
(recipes) for outgoing e-mails.

I want to do
1. reject all mails coming from some users except to a public domain,
2. send a copy of outgoing messages to a specific address also,
3. add a text string at the end of the outgoing messages.

Any body can help me?

Volkan Evrin