Custom fields

I ahve a custom field called question_file and i would liek to get the value from it for my quiz.
here is the code that does that but it does not get the right question file data.
Please can anyone tell me why?
Thanks
.matt

global $questions, $rankings, $question_string,

$submit_button_string, $intro_string;
$question_file = get_post_custom_values(“question_file”);
if (!isset($question_file)) {
$question_file[0] = ‘wb_quiz_questions.php’;
$question_file[1] = ’emo.php’;
}
require($question_file[0]);