I am trying to add the new Facebook log in button to my registration page on my Drupal site. I know the following code is wrong, but I don't know the right syntax to implement it: function facebook_user($op, &$edit, &$user, $category = NULL) { switch($op) { // User is registering. case 'register': // Add a Facebook login button. echo ' '; } } What should I use instead of echo? Is there another way I should be going about this? Thanks