code: public function destroy()
  	{
  		session_start();
  
  		$_SESSION = array();
  		
  		if (ini_get("session.use_cookies")) {
  		    
  			$aParams = session_get_cookie_params();
  		    
  		    setcookie(session_name(), '', time() - 42000,
  		        $aParams["path"], $aParams["domain"],
  		        $aParams["secure"], $aParams["httponly"]
  		    );
  		}
  
  		session_destroy();
  	}
docs: destroy the session
  
  @access public
  @return mixed