FaceBook Connect

Bonjour suite à ton tuto j'ai une erreur mais en récupérant les sources :

An Internal Error Has Occurred
Error: An Internal Error Has Occurred.
Stack Trace
#0 G:\Sites\Facebook\app\Lib\Facebook\facebook.php(18): require_once()
#1 G:\Sites\Facebook\app\Controller\UsersController.php(23): require('G:\Sites\Facebo...')
#2 [internal function]: UsersController->facebook()
#3 G:\Sites\Facebook\lib\Cake\Controller\Controller.php(476): ReflectionMethod->invokeArgs(Object(UsersController), Array)
#4 G:\Sites\Facebook\lib\Cake\Routing\Dispatcher.php(106): Controller->invokeAction(Object(CakeRequest))
#5 G:\Sites\Facebook\lib\Cake\Routing\Dispatcher.php(88): Dispatcher->_invoke(Object(UsersController), Object(CakeRequest), Object(CakeResponse))
#6 G:\Sites\Facebook\app\webroot\index.php(96): Dispatcher->dispatch(Object(CakeRequest), Object(CakeResponse))
#7 {main}

J'ai regarder mon code et je croie que le problème viens du require

require APPLIBS.'Facebook'.DS.'facebook.php';