How can i configure my exchange server 2003 to restrict some users to send to specific email address within the same organization?

John: I belive that you can restrict users to send mail to some email address internally. But you can block those recpeinets to accept mails from the user. http://support.microsoft.com/kb/827616

John: I believe that we can not restrict user to send message to some email address internally part of this we can block message on the recipients so they will net able to receive message from these users. http://support.microsoft.com/kb/827616