NS4 = (document.layers) ? 1 : 0;
IE4 = (document.all) ? 1 : 0;
ver4 = (NS4 || IE4) ? 1 : 0;
isIE5 = (document.all && document.getElementById) ? true : false;
isNS6 = (!document.all && document.getElementById) ? true : false;

function goLayer(menuName,on) {
                if (on) {
                        if (NS4) {
                                document.layers[menuName].visibility = "show";
                        } else if (isIE5 || isNS6){
								  elm = document.getElementById(menuName);
 								  elm.style.visibility = "visible";

						} else {
                                document.all[menuName].style.visibility = "visible";
                        }
                } else {
                        if (NS4) {
                                document.layers[menuName].visibility = "hide";
                        } else if (isIE5 || isNS6){
								  elm = document.getElementById(menuName);
 								  elm.style.visibility = "hidden";								
                        } else {
                                document.all[menuName].style.visibility = "hidden";
                        }
                }
}