出错了，谁来帮帮我呀？

Fatal error: spl_autoload(): Class Test could not be loaded in /home/cabox/workspace/php/spl/Autoload01.php on line 10 

怎么办呀？ 

<?php spl_autoload_extensions('.class.php'); set_include_path(get_include_path().PATH_SEPARATOR."libs/"); spl_autoload_register(); new Test();