var xmlHttp;

function stateChanged() { 
	if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { 
		document.getElementById("signup").innerHTML=xmlHttp.responseText 
	} 
}

function GetXmlHttpObject() {
	var xmlHttp=null;
	try {
		// Firefox, Opera 8.0+, Safari
		xmlHttp=new XMLHttpRequest();
	}
	catch (e) {
		//Internet Explorer
		try {
			xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e) {
			xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
		}
	}
	
	return xmlHttp;
}

function getSignup() {
	if (CheckEmail(document.newsletter.email.value)) {
		xmlHttp = GetXmlHttpObject();
		if (xmlHttp == null) {
			alert("Browser does not support HTTP Requests");
			return;
		}
		
		var url = "mail.php?e=" + document.newsletter.email.value + "&type=signup&ran=" + Math.random();
		xmlHttp.onreadystatechange = stateChanged;
		xmlHttp.open("GET", url, true);
		xmlHttp.send(null);
	} else {
		alert("Not a valid email address.");
	}
}

function CheckEmail(email) {
	AtPos = email.indexOf("@");
	StopPos = email.lastIndexOf(".");
	
	if (AtPos == -1 || StopPos == -1) {
		return false;
	} else {
		return true;
	}
}