function ajaxQuery(params) {
	http.open("POST", "/includes/ajax_functions.php", true);
	http.onreadystatechange = ajaxHandler;
	http.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	http.send(params);
}

function ajaxHandler() {
	if ( http.readyState == 4 ) {
		//document.getElementById('divTest').innerHTML = http.responseText;
		//alert(http.responseText);
		var xml = http.responseXML.getElementsByTagName('result')[0];
		var action = http.responseXML.getElementsByTagName('result')[0].getAttribute("action");
		switch(action) {
			case 'getModels':
				rmrDisplayModels(xml);
				break;
		}
	}
}

function rmrDisplayModels(xml) {
	var inputN = document.getElementById("model");
	inputN.options.length = 0;
	var resultcount = xml.getElementsByTagName("model").length;
	var newOpt;
	
	for(i = 0; i<resultcount; i++) {
		newOpt= document.createElement('option');
		tmpNode = xml.getElementsByTagName("model")[i];
		newOpt.value = tmpNode.getElementsByTagName("id")[0].childNodes[0].nodeValue;
		newOpt.text = tmpNode.getElementsByTagName("modelname")[0].childNodes[0].nodeValue;
		try {
			inputN.add(newOpt, null);
		} catch(ex) {
			inputN.add(newOpt);
		}
	}
}