addEventListener to radio button

I have 3 <INPUT> elements all of type "radio" and with the same "name". I want
to catch an event whenever a new selection is made. The values of the input
fields are "one", "two", "three". I start with the <INPUT> "one" selected. When
I click on "two" or "three" the event gets directed to my event listener but the
value of the "radio" is still "one". No matter what I click, the value is always
returned as "one". It seems that the event is firing when a radio button is
clicked but before the selected value has been changed. Any ideas on what may be
happening or how to work around it?

Thanks,
David Robison