Allow selected Computers to access the application on Server

Allow selected Computers to access the application on Server

We have installed our WPF application on Windows Server 2003 (installed to
Everyone, not Just Me). Windows Server have many Domain Users and Computer
on LAN.
How can I allow selected PCs (not Domain Users) on Domain to access the
application using Remote Desktop ? I tried to make Computer Names as
Application Users, but problem arises when two computer have same names.
Initially I tried to restrict it with Domain Users, but problem was the
Domain Users can connect to Server via Remote Desktop from any PC.
Thanks in advance.