var reqObj;
  function doSearch(control) {
		var code = document.form3.category_id.value;
		var parms = '?code=' + code;
	  setupReqObject(searchedListener, 'retrieve_subcategories.php' + parms, true);
		reqObj.send();
	}


  function searchedListener(){
    if (reqObj.readyState == 4) { // Complete
      if (reqObj.status == 200) { // OK response
        populateDropList('sub_category',reqObj.responseText);
      } else {  
        alert("The server returned an invalid response.  Please try again.");
      }    
    }
  }	
	
  function populateDropList(control,text) {
		returnElements=text.split(";")
		document.getElementById(control).options.length=0
		for ( var i=0; i<returnElements.length; i++ ) {
			valueLabelPair = returnElements[i].split("|");
			document.getElementById(control).options[i] = new Option(valueLabelPair[1], valueLabelPair[0]);
		}
	}
	
	function searchThisCat(catId) {
	  document.form3.category_id.value = catId;
		document.form3.button1.click();
	}
	
	if (document.layers)  {
		document.captureEvents(Event.KEYDOWN);
  }
  
	document.onkeydown =  function (evt) {
		var keyCode = evt ? (evt.which ? evt.which : evt.keyCode) : event.keyCode;
		if (keyCode == 13) { 
			document.form3.button2.focus();
			document.form3.button2.click();
		}
		else {
			return true;  
    }
  };