function ajaxInit() {
	var req;
	try {
		req = new ActiveXObject("Microsoft.XMLHTTP");
	} catch(e) {
		try {
			req = new ActiveXObject("Msxml2.XMLHTTP");
		} catch(ex) {
			try {
				req = new XMLHttpRequest();
			} catch(exc) {
				alert("Esse browser não tem recursos para uso do Ajax");
				req = null;
			}
		}
	}
	return req;
}

function gE(ID) {
	return document.getElementById(ID);
}

function gEs(tag) {
	return document.getElementsByTagName(tag);
}

function loading(opt, tag) {
	if (opt == true) {
		var refer = gE(tag);
		var referHeight = refer.offsetHeight;
		refer.style.textAlign = 'left';
		var img = document.createElement('img');
		img.setAttribute('src','images/ajax-loader.gif');
		img.setAttribute('id','loading');
		img.setAttribute('width','24');
		if (!document.getElementById('loading')) {
			refer.insertBefore(img, refer.firstChild);
		}
	} else if (opt == false) {
		var imgLoading = gE('loading');
		if (imgLoading) {
			imgLoading.parentNode.removeChild(imgLoading);
		}
	}
}