function liveUpdater(uriFunc, ret)
{
	var request = false;

	function xmlUpdater()
	{
		return sendHttpCallback(uriFunc(), ret);
	}
	return xmlUpdater;

	//	Build and send HTTP request to Seaside

	function sendHttpCallback(uri, ret, respFunc)
	{
		if (request && request.readyState < 4)
			request.abort();
		request = newHttpRequest();
		if (!request)
			return ret;
		if (!respFunc)
			respFunc = processRequestChange;
		request.onreadystatechange = respFunc;
		// Resolve xml entity before issuing the request
		var uri = addParameter(uri, "timestamp", (new Date()).getTime().toString());
		var regex = new RegExp("&amp;", "g");
		uri = uri.replace(regex,"&");
		request.open("GET", uri);
		request.send(null);
		return ret;
	}

	//	Parse HTTP response from the Seaside live callbacks as XML and update the document

	function processRequestChange()
	{
		if (request.readyState == 4) {
			var doc = request.responseXML;
			var replacements = [];
			var anyReplacement = false;
// alert( request.responseText);
// alert( request.status);
// alert( request.statusText);
// alert( request.getAllResponseHeaders() );	
// alert( request.responseXML.parseError.errorCode);
// alert( request.responseXML.parseError.reason);
			if (doc != null) {
				var elements = doc.getElementsByTagName("*");
				if (elements.length == 0) {
					// IE does not support the above, use an alternative hard-coded technique
					elements = getAllElements(doc)
				}
				// Find html elements with the id= attribute
				for ( var x = 1 ; x <= elements.length ; x++ ) {
					var elem = elements[x-1];
					if (elem.tagName == "body") {
						var body = xmlString(elem);
					}
					var attributes = elem.attributes;
					if (attributes.length > 0) {
						for ( var ax = 1 ; ax <= attributes.length ; ax++ ) {
							var attr = attributes[ax-1];
							var attrName = attr.name;
							if (attrName == "id") {
								// Find the html element in the document that has a matching id and replace it
								var docElement = document.getElementById(attr.value);
								if (docElement) {
									if (!includes(replacements,elem)) {
										// HTML is only updated with the parent at highest level
										// Resolve IE and Opera issue where <br></br> skips two lines
										var regex = new RegExp("<br></br>", "g");
										var replacement = xmlString(elem).replace(regex,"<br/>");
										try {
											docElement.innerHTML = replacement;
											anyReplacement = true;
											replacements[replacements.length] = attr.value;
										} catch (e) {
											// Some browsers (like Safari) have read-only elements
										}
									}
								}
							}
						}
					}   
				}
				// Find html <script> elements and execute them
				for ( var x = 1 ; x <= elements.length ; x++ ) {
					var elem = elements[x-1];
					if (elem.tagName == 'script') {
						eval(elem.childNodes[0].data);
					}
				}
			}
			if (!anyReplacement) {
				if ( body ) {
					document.body.innerHTML = body;
				} else {
					// Most probable reason for being here : response does not have an xml content
					// For instance : an exception in the live callback
					document.body.innerHTML = request.responseText;
				}
			}
		}
	}
}