autoabacus

I just encountered this problem also, but found a cause and solution. I was using radio buttons and other input elements on a page where the data was being posted via Ajax, and I did not need a form. However, the lack of a form tag caused this Firefox (4) problem i.e. checked='checked' was ignored on radio button inputs. Chrome was OK. I didn't check other browsers. Adding a form tag to the page fixed the issue with Firefox. As inputs are supposed to be form elements, the behaviour is understandable. Perhaps this was also the cause of the original poster's problem.