facebook application

I need a pretty simple facebook application. I have a community, which not everybody can be a member. I want to let promote my community from the members of my community. This means, only members of my community should have the possibility to add this application to his facebook profile. If added, a flash should be shown e.g. "proude member of xxxxx" in the profile of the facebook user. To make sure, that only members of my community can add this application (otherwise it would not make much sense), the user who want to add the application has to enter the username of his account on my community, then the application has to send a request to my community system with the username. If the username exists, the user will get an email from my system with an activation link. If he confirm his account with this link, the facebook application has to be shown in his facebook profile. The scope of this project is only the facebook part. I would do the rest (provide the interface for request an activation link mail and create the flash which has to be shown. If you have questions feel free to ask. Only develeopers with good experiences on facebook apps will be accepted.