No I don't think you can.
You can of course decide whether the user in question should receive
messages from everyone or only certain users, you can also specify them not
to receive messages from certain individuals.
You could send a message with the 'sensitivity' option set to 'private'
which stops them modifying a message then forwarding it on.
The best way is to educate them in what to forward and what not too.
>Is there any way to deny the forward option on certain messages or all
>There was an incident at work recently that sent the admins and CIO running
>mad and I need to know if there is a way in Exchange 5 to controll reply,
>forward and such things from an administrative angle??