Suppress "A session had already been started" PHP notice

 uphpCAS.php

@@ -123,7 +123,7 @@
    }
    
    public function logout($returnUrl = NULL) {
        session_start();
        @session_start();
        if($this->isAuthenticated()) {
            unset($_SESSION[$this->sessionName]);
            header('Location: '.$this->logoutUrl($returnUrl));
@@ -139,7 +139,7 @@
    }
    
    public function authenticate() {
        session_start();
        @session_start();
        if($this->isAuthenticated()) {
            return $_SESSION[$this->sessionName];
        } elseif(isset($_REQUEST['ticket'])) {