Validation warning on acceptance checkbox – CF7

I am currently having difficulty getting a validation warning to work on the acceptance check box.

Validation works fine throughout the rest of the form however it doesn’t show a warning against the acceptance box went it hasn’t been checked. The form technically works fine as when the box is checked it submits and when its not checked it doesn’t. It just doesn’t have the visual warning which the other fields in the form have.

Has anyone come across this before?

You can find the form here: http://dev.gurucareersnetwork.com/testing-page/

http://wordpress.org/extend/plugins/contact-form-7/