function openAjax() {
	if (window.XMLHttpRequest) { // Mozilla, Safari,...
		ajax = new XMLHttpRequest();if (ajax.overrideMimeType) {ajax.overrideMimeType('text/xml');}
	}else if (window.ActiveXObject) { // IE
		try {ajax = new ActiveXObject("Msxml2.XMLHTTP");} 
		catch (e) {try {ajax = new ActiveXObject("Microsoft.XMLHTTP");} catch (e) {}}
	}return ajax;
}

function gravaNews(metodo,pagina, email, nome){
	 var ajax = openAjax();
	 if(email.value.length>3){
		if(nome.value.length>0){
			  pagina += '?email='+email.value+"&nome="+nome.value;
			  email.value="";
			  nome.value="";
			  ajax.open(metodo,String(pagina),true);
			  ajax.onreadystatechange = msgRetorno;
			  ajax.send(null);			 
		}else{
		   alert("Informe nome e email!");			    
		}  
	 }
}

function msgRetorno(){
	 if(ajax.readyState ==4){
		if(ajax.status==200){
			var aviso = ajax.responseText;
			alert(aviso);
	    }   
      }
}