Let say you have this kind of JSON file :

{"10233401":"10010","10001101":"5519"}

And you use this code in jQuery to fill your select element named "debugSelect":

$.getJSON("data.json", function(data){
  $.each(data, function(key, value) { options += "<option value='"+key+"'>"+value+"</option>"; });
  $("#debugSelect").html(options);
});

Expected Result : 10010

FF Show : 10010

IE/Chrome show : 5519

I spent 2 days to find this. I suppose that IE Ajax part sort the JSON result. IMHO it may be better to use the sorting order given by the JSON file.

Thanks.