Wordpress Ajax comment post - PHP for functions.php

add_action('comment_post', 'ajaxify_comments',20, 2);
function ajaxify_comments($comment_ID, $comment_status){
    if(!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest'){
    //If AJAX Request Then
        switch($comment_status){
            case '0':
                //notify moderator of unapproved comment
                wp_notify_moderator($comment_ID);
            case '1': //Approved comment
                echo "success";
                $commentdata=&get_comment($comment_ID, ARRAY_A);
                $post=&get_post($commentdata['comment_post_ID']);
                wp_notify_postauthor($comment_ID, $commentdata['comment_type']);
            break;
            default:
                echo "error";
        }
        exit;
    }
}