I'm following along with the Railscast for Simple OmniAuth (in text format here: <http://asciicasts.com/episodes/241-simple-omniauth>). Everything works perfectly until I add the Facebook login. When trying the "Login With Facebook" link I get the following error.

Invalid redirect\_uri: Given URL is not allowed by the Application configuration.

The URL of my page with the login link is 'http://mluton.example.com:3000/characters/'. In my Facebook app's website settings I have the Site URL set to 'http://mluton.myfitv.com:3000/auth/facebook/callback/'. The trailing slash is required. This is what omniauth will set as the callback when making its authentication request. However, if I look at the URL on the page with the above error I see this at the end.

redirect\_uri=http%3A%2F%2Fmluton.example.com%3A3000%2Fauth%2Ffacebook%2Fcallback

No trailing slash. Is there a disconnect between omniauth and Facebook or am I missing something? Is there a way to override the default callback url omniauth generates?