I have setup a postfix server that uses mysql using this tutorial:howtoforge.com/virtual-users-and-domains-with-postfix-courier-mysql-and-squirrelmail-centos-6.0-x86_64

Postfix is running now and can send and receive mail succesfully

Now I want to add the following to my postfix.
In my database I created 2 extra field per mailbox. Named add_footer and suspended.

For the add_footer: When a user sends an email and the add_footer is 1, I want to append some small disclaimer to the email.

For the suspended: When the users suspended field is set to 1, I want to bounce all outgoing and incoming mails for that mailbox with an error that the account is suspended.

How can I do this?
I have searched the internet but still cannot figure out where and how to do this. Any help would be appreciated.