[jQuery] Caching?

[jQuery] Caching?

Hello!
   I need to load a value (returned by a php script) into a
textbox each 10 seconds, and reload web if this value change. I'm using
next code:
<script src="jquery.js"></script>
<script>
$(document).ready(function()
{
   //ajaxTime.php is called every second to get time from server
   var refreshId = setInterval(function()
   {
     $.get("contar.php?accion=respuestas", function(data){
                $('#txtNuevo').val(data);  
                if(parseInt($('#txtNuevo').val()) > parseInt($('#txtUltimo').val())){
                        window.location.reload()  
                }
                });
   }, 10000);
   //stop the clock when this button is clicked
   $("#stop").click(function()
   {
     clearInterval(refreshId);
   });
});
</script>
I have got one problem because it only loads the value
first time. After that, no more loads new values. I think the problem
is produce because Internet Explorer caches the web and reload old
value. It works fine with Firefox, but I need make it work with IE too.
Is there any way to force reload not cached data from code?
Regards