var IE = navigator.appVersion.indexOf("MSIE") > 0;

ns4 = (document.layers)? true:false
ie4 = (document.all)? true:false

function preload(imgObj,imgSrc) {
	if (document.images) {
		eval(imgObj+' = new Image()');eval(imgObj+'.src = "'+imgSrc+'"')
		}
	}

function swapImg(layer,imgName,imgObj) {
	if (document.images) {
		if (!IE && layer!=null) eval('document.'+layer+'.document.images["'+imgName+'"].src = '+imgObj+'.src')
		else {document.images[imgName].src = eval(imgObj+".src")}
		}
	}

function show(id) {
	if (ns4) document.layers[id].visibility = "show"
	else if (ie4) document.all[id].style.visibility = "visible"
}

function hide(id) {
	if (ns4) document.layers[id].visibility = "hide"
	else if (ie4) document.all[id].style.visibility = "hidden"
}