var xmlhttp;
var callbackfunction;

if (window.XMLHttpRequest) {

	// If IE7, Mozilla, Safari, etc: Use native object
	var xmlhttp = new XMLHttpRequest();

}
else {
	if (window.ActiveXObject) {
		// ...otherwise, use the ActiveX control for IE5.x and IE6
		var xmlhttp = new ActiveXObject('Microsoft.XMLHTTP');
	}
}

function httpget(page,callback) {

	callbackfunction = callback;
	if (xmlhttp != null) {
		if (typeof (callback) == 'undefined') {
			xmlhttp.open('GET', page, false);
			xmlhttp.setRequestHeader('If-Modified-Since', 'Tue, 11 Jul 2000 18:23:51 GMT');
			xmlhttp.send('');
			return xmlhttp.responseText;
		}
		else {
			xmlhttp.open('GET', page, true);
			xmlhttp.setRequestHeader('If-Modified-Since', 'Tue, 11 Jul 2000 18:23:51 GMT');
			xmlhttp.onreadystatechange = xmlhttpreturn;
			xmlhttp.send('');
		}
	}
	else {
		alert('Your browser does not support XMLHTTP.');
	}
}
function httppost(page, post, callback) {

	callbackfunction = callback;
	if (xmlhttp != null) {
		if (typeof (callback) == 'undefined') {
			xmlhttp.open('POST', page, false);
			xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
			xmlhttp.setRequestHeader('If-Modified-Since', 'Tue, 11 Jul 2000 18:23:51 GMT');
			xmlhttp.send(post);
			return xmlhttp.responseText;
		}
		else {
			xmlhttp.open('POST', page, true);
			xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
			xmlhttp.setRequestHeader('If-Modified-Since', 'Tue, 11 Jul 2000 18:23:51 GMT');
			xmlhttp.onreadystatechange = xmlhttpreturn;
			xmlhttp.send(post);
		}
	}
	else {
		alert('Your browser does not support XMLHTTP.');
	}
}
function xmlhttpreturn() {
	if (xmlhttp.readyState == 4) {
		if (xmlhttp.status == 200) {
			callbackfunction();
		}
		else {
			alert('The system was unable to retrieve the relevant list');
			document.write(xmlhttp.responseText);
		}
	}

}
function doc(id) {
	return document.getElementById(id);
}