function showData(params, combo_ID, sel_ID){
		
		document.getElementById(combo_ID+"_load").style.display = ""
		
	var xmlhttp;    

	if (params==""){
	  document.getElementById(combo_ID).innerHTML="";
	  return; }
	  
	if (window.XMLHttpRequest){
		// code for IE7+, Firefox, Chrome, Opera, Safari
	  xmlhttp=new XMLHttpRequest();}
	else{
		// code for IE6, IE5
	  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");}
	  
	xmlhttp.onreadystatechange=function(){
	  if (xmlhttp.readyState==4 && xmlhttp.status==200){
		  PopulateCountryList(xmlhttp.responseXML.documentElement, combo_ID);
		}
	  }
	  	
		//get_transport_models
		//get_locations
		
		xmlhttp.open("GET","/Includes/ajax/get_listdata.asp?"+params+"&sel_ID="+sel_ID,true);
		xmlhttp.send();
}

// populate the contents of the country dropdown list
function PopulateCountryList(countryNode, combo_ID)
		{
			
			var countryList = document.getElementById(combo_ID);
			// clear the country list 
			for (var count = countryList.options.length-1; count >-1; count--)
			{
				countryList.options[count] = null;
			}
		
			var countryNodes = countryNode.getElementsByTagName('item');
			var idValue;
			var textValue; 
			var sel;
			var optionItem;
			// populate the dropdown list with data from the xml doc
			for (var count = 0; count < countryNodes.length; count++)
			{
				textValue = GetInnerText(countryNodes[count]);
				idValue = countryNodes[count].getAttribute("id");
				sel = countryNodes[count].getAttribute("sel");
					var opt = document.createElement("option");
					opt.text = textValue;
					opt.value = idValue;
					opt.selected = sel;
					countryList.options.add(opt);
			}
			
				document.getElementById(combo_ID+"_load").style.display = "none"

}
		
// returns the node text value 
function GetInnerText (node)
		{
			 return (node.textContent || node.innerText || node.text) ;
}