function createXMLHTTP() {
	var ajax;
	
	try {
		ajax = new ActiveXObject("Microsoft.XMLHTTP");
	} catch(e) {
	   try {
		   ajax = new ActiveXObject("Msxml2.XMLHTTP");
		   alert(ajax);
	   } catch(ex) {
		   try {
			   ajax = new XMLHttpRequest();
		   } catch(exc) {
				alert("Esse browser nao tem recursos para uso do Ajax");
				ajax = null;
		   }
	   }
	   return ajax;
	}

   	var arrSignatures = ["MSXML2.XMLHTTP.5.0", "MSXML2.XMLHTTP.4.0",
					  "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP",
					  "Microsoft.XMLHTTP"];

  	for (var i=0; i < arrSignatures.length; i++) {
	   try {
		   var oRequest = new ActiveXObject(arrSignatures[i]);
		   return oRequest;
	   } catch (oError) {}
   	}

	throw new Error("MSXML is not installed on your system.");
}

function divAjax(div, endereco) {
	var obj = createXMLHTTP();
	
	obj.open("post", endereco, true); 
	obj.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

	obj.onreadystatechange=function() {
		if (obj.readyState==4) {
			document.getElementById(div).innerHTML = obj.responseText;
		}
	}
	obj.send("");
}

function listaCidade(estado) {	
	var action = '/cidade.php?estado=' + estado;
	divAjax('cidade', action);	
}

function logado() {	
	divAjax('logado', "/../logado.php");
}