function ajaxFunction() {
var xmlHttp;
try {
// Firefox, Opera 8.0+, Safari
xmlHttp=new XMLHttpRequest();
return xmlHttp;
} catch (e) {
// Internet Explorer
try {
xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
return xmlHttp;
} catch (e) {
try {
xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
return xmlHttp;
} catch (e) {
alert("Tu navegador no soporta AJAX!");
return false;
}}}
}

function Enviar(_pagina,capa) {
    var ajax;
    ajax = ajaxFunction();
    ajax.open("get", _pagina, true);
    ajax.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

    ajax.onreadystatechange = function() {
		if (ajax.readyState==1){
			document.getElementById(capa).innerHTML = " Aguarde por favor...";
			     }
		if (ajax.readyState == 4) {
		   
                document.getElementById(capa).innerHTML=ajax.responseText; 
		     }}
			 
	ajax.send(null);
}