Configure Nginx for SSL on Ruby on Rails app using Passenger/Capistrano/Ubuntu VPS

I have deployed a Ruby on Rails app on a Ubuntu VPS using nginx, Capistrano and Passenger. However I have not been able to configure nginx/Passenger to deal with SSL correctly. Only certain actions on the Rails app require SSL and the app currently forces the redirect to use SSL for those actions. However Rails cannot pick up the SSL request now using nginx and Passenger so it goes into an infinite redirect loop on Firefox and Chrome. Also the commercial SSL certificate I have only caters to a non-www domain and appended www to my domain throws up security warnings. I have written a redirect in Rails to cater to such a situation but have not tested. If it does not work then the rewrite must be done in nginx. The SSL certificate is already generated and installed on the server. Finally for non-SSL request I believe some browsers have problem accessing the non-www domain but the appended www domain works fine. This is most likely a bad configuration of nginx and will need to be fixed. Access to the configuration is through SSH on an Ubuntu environment and terminal. I will provide a user account for you with sudo access.