[Javascript] Why IE doesn't fire the event ?

[grillo at gmail.com (Marcelo Wolfgang)]

Hi list,

I'm working on a web page that has some radio buttons with a onchange
event, that is acting weird, and I need some advice

They work fine in Firefox, but in IE they only fire after there's
another click on the page, something like this:

- click in one radio (nothing happens)
- click anywhere on the page, may be another radio, or the background,
the event is fired

the page in question is :

http://work.grillo.tk/gaiolla/checkout_shipping.html

Thanks for any advice.
Grillo