This plugin is nonsense

Yes there is:

http://core.svn.ww.wp.xz.cn/tags/3.7.1/wp-includes/pluggable.php

inside wp_check_password():

return apply_filters('check_password', $check, $password, $hash, $user_id);

I also just tested and used the plugin successfully on WP 3.7.1.

David