function doLogin(user, pass, layerID) {
	var layername = document.getElementById(layerID);
	if(user.value != "" && pass.value != "") {
		var starttop = (screen.availHeight - 740)/2 - 1;
		var startleft = (screen.width - 1000)/2 - 1;  //1000 = width 990 + Browser Border 10
		var width=990;
		var height=691;
		var f1 = window.open('home.html','_blank','width=' + width + ',height=' + height + ',left=' + startleft + ',top=' + starttop + ',toolbar=no,menubar=no,scrollbars=no,statusbar=no,resizable=yes');
	} else {
		if(user.value == "") {
			layername.style.display = "block";
			user.focus();
		}
		if(pass.value == "") {
			layername.style.display = "block";
			pass.focus();
		}
		if(user.value == "" && pass.value == "") {
			layername.style.display = "block";
			user.focus();
		}
		if(user.value != "" && pass.value != "") {
			layername.style.display = "none";
		}
	}
}