var myHttpRequest = false;
var state = 'hidden';

if(window.XMLHttpRequest)
     myHttpRequest = new XMLHttpRequest();
else if(window.ActiveXObject)
     myHttpRequest = new ActiveXObject("Microsoft.XMLHTTP");

function hide(layer_ref) {

		state = 'hidden';
		
	if (document.all) { //IS IE 4 or 5 (or 6 beta)
		eval( "document.all." + layer_ref + ".style.visibility = state");
	}
	if (document.layers) { //IS NETSCAPE 4 or below
		document.layers[layer_ref].visibility = state;
	}
	if (document.getElementById &&!document.all) {
		hza = document.getElementById(layer_ref);
	hza.style.visibility = state;
}
}

function show(layer_ref) {

		state = 'visible';

	if (document.all) { //IS IE 4 or 5 (or 6 beta)
		eval( "document.all." + layer_ref + ".style.visibility = state");
	}
	if (document.layers) { //IS NETSCAPE 4 or below
		document.layers[layer_ref].visibility = state;
	}
	if (document.getElementById &&!document.all) {
		hza = document.getElementById(layer_ref);
	hza.style.visibility = state;
}
}