reCAPTCHA not working in popup window

I found a solution for the problem. Just add this small snippet to
your form:

'
script type='text/javascript'>
Recaptcha.create("yourkey",
"recaptcha_div", {
theme: "red",
callback: Recaptcha.focus_response_field
});

/script>

And add this to the header:

script type="text/javascript"
src="http://api.recaptcha.net/js/recaptcha_ajax.js">/script>
http://groups.google.com/group/recaptcha/browse_thread/thread/876aa8084523b0ec/00cfbef150f060b9?lnk=gst&q=recaptcha+dynamic&pli=1