Banning system

Hi. I need you to develop a small application for me. my clients will install this application on their personal computers. inside this application, we will embedd a flash web page ( which is web based flash chat room. ) The Flash web page will be in a password protected directory on my server. That flash web page can not be opened directly from browser since that is a password protected directory. This application will be with builtin User name and Password to access that directory. Why i need this application is to make a Power full banning system in this application. Whenever a user try to go to password protected directory, The application will search for Banned MAC address ( or processor ID or something similer ) in my server . If clients MAC address is in BAN list in my server, the application will not be opened. And will give error " You are banned " . If client's MAC address is not in the Banned list, he can simply login to our website. I DON'T want to Block IP address or hostname. since this is not a good option.