The problem is only in 1.6 version of jQuery,

when you try to uncheck a radio button so:

$('input[type="radio"]').checked = false;

or

$('input[type="radio"]').attr('checked',false);

or

$('input[type="radio"]').removeAttr('checked');

all this ways doesnt work in 1.6 version, but when change

the library versin for other, the same code works perfectly!!!