Jquery problem. Working in IE not in FF

Jquery problem. Working in IE not in FF

HI,
I am trying to use an ajax call this works perfectly in IE but in FF and Safari it throws an error with text "error" does not make me wiser.
Tried everything but it seems I am doing something wrong for FF
the code
 
  1. Drupal.behaviors.dynamic_counter = function(context) {
        $('a.download').click(function () {
            var urlget = '/counter/get';
            $.ajax({
                type: 'GET',
                url:  urlget,
                dataType: 'json',
                success: function(data) {
                    alert (data.counter);
                },
                error: function(xmlhttp) {
                    alert('An error occured: ' + xmlhttp.status);
                }
            });
        });
    }














There is no difference if I use $.get or leave drupal out of it it just does not work for FF

help please