Is your Facebook Canvas area setup properly? Mainly, make sure you've gone through the "Requirements" and "Migration Settings" sections of the following document:
www.sourcecoast.com/jfbconnect/docs/facebook-requests
If either of those sections aren't setup properly, including having an SSL certificate installed on your site, Requests will not fully work.
Hope that helps get you started, but if you have any more questions, just let us know.
Thanks,
Alex