Update: Unfortunately, it works well at first sight.
With the default WordPress 3.0 Twenty Ten theme, the plugin empties the body class:
before
<body class="home blog logged-in">
after
<body class="" onload="HumansNotBots()" id="htmlbody">
With the current Hybrid theme, it seems to interfere with Hybrid’s own action hooks–it doesn’t insert anything.
There must be a better way to load and run the script, maybe wp_enqueue_script?
https://codex.www.ads-software.com/Function_Reference/wp_enqueue_script
HTH ??