I have installed facebook application that you can find here: [url removed, login to view] .
It works well except one thing. If a user send invitation to hes friends they receive invitation but they get redirected to a error page.
I am sure that for somebody who knows facebook applications can be fixed in minutes...
PS. If you have 2 facebook accounts you can go at the app link and invite your self. After you accept invitation link you will see the problem.