function getXMLHttp(){
	var xmlHttp;
	try{
		//Firefox, Opera 8.0+, Safari
		xmlHttp = new XMLHttpRequest();
	}
	catch(e){
		//Internet Explore
		try{
			xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch(e){
			try{
				xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch(e){
				alert("Your browser does not support AJAX!")
				return false;
			}
		}
	}
	return xmlHttp;
}
function showNewsletter(newsletterURL){
	var xmlHttp = getXMLHttp();
	xmlHttp.onreadystatechange = function(){
		if(xmlHttp.readyState == 4){
//this is the output (after call below)
			handle_ajax_update(xmlHttp.responseText, newsletterURL);
		}
	}
//this is the input
	xmlHttp.open("GET", newsletterURL, true);
	xmlHttp.send(null);
}
function handle_ajax_update(response, newsletterURL){
	document.body.innerHTML = '<iframe src="'+newsletterURL+'" frameborder="0" style="position: absolute; top:0px; left:0px; width:100%; height: 100%; margin:0; padding:0;"></iframe>';
}