I'll try this one more time

Could anyone answer my question regarding this issue? I want to allow one single email adres to be able to mail to all domainnames possible, but the rest mustn't be able to. So,
johndoe@domain.com would be able to send email to wherever he desires to, yet
janedoe@domain.com shouldn't be able to. I already managed to configure Postfix so there are only 3 domains allowed to email through the system. They may send email to the same 3 domains only.
Any tips?