TOPIC: Default captcha not renewing image

For some reason the javascript to renew the image when you click on the captcha image (using the default captcha option - applicable to all users) does not work. It does not change the image.
No javascript conflict error messages appear (I use debugging on IE8, but the problem is the same on Firefox.) which is the normal problem on my site due to the other extensions I have, so I don't know why the image replacement does not happen.
I have enabled Akismet with an id supplied by Akismet, but that does not appear to make any difference.
Any ideas?

I will need a link to debug this one, but why don't you try to use recaptcha? To be honest I like recaptcha more than our default captcha - they definitely do the job better than we do, so I'm even thinking of removing the default captcha in one of the next releases

Cheers,
Daniel

Great idea- I've changed to reCaptcha and that works fine.