Restricting a Exchange 5.5 User

Can some body help me to find out the solution, I shall be very thankful.

I have the NT Server 4 (SP5 installed) & Exchange 5.5 (SP 1) on the client side is Windows 95 with outlook 97.

I want to do:

1. Restrict a single NT user for sendingand receiving to a specific email address like xyz@hotmail.com he should not be able to accept or send any other mail to any other address.

2. Above User should only send and receive mail on a specific time like from 5:00pm to 7:00pm