HTML/Javascript app that runs on the filesystem, security issue

Access to restricted URI denied" code: "1012

$.get(productUrl, function (data)
    	{
    		alert (data);
    	}
    );

python -c “import SimpleHTTPServer;SimpleHTTPServer.test()”

<script>
 function callback(str)
 {
  alert(str);
 }
 function makeRequest(param)
 {
  var s = document.createElement('script');
  s.src = 'http://serveranywhere/script.bla?' + params;
  document.getElementsByTagName[0].appendChild(s);
 }
</script>

callback('<xml><that><does><something></something></does></that></xml>');