setParameter()

Hi guys and gals,

The following javascript code should retrieve a querystring value and 
assign its value to a xsl:param in a stylesheet, but its not changing 
the value of sector can anyone identify why?


  var myXMLHTTPRequest = new XMLHttpRequest();
  myXMLHTTPRequest.open("GET", "example.xsl", false);
  myXMLHTTPRequest.send(null);

  xslStylesheet =myXMLHTTPRequest.responseXML;
  xsltProcessor.importStylesheet(xslStylesheet);

  if (getURLParams("s") !=null)
  { 
   xsltProcessor.setParameter(null, "sector", getURLParams("s"));

   myXMLHTTPRequest =new XMLHttpRequest();
   myXMLHTTPRequest.open("GET", "exmaple.xml", false);
   myXMLHTTPRequest.send(null);
  }

regards
Luke