dom = (document.getElementById)? true : false;
nn4 = (document.layers)? true : false;
ie4 = (!dom && document.all)? true : false;

var maxmenu = 5;
var start = 0;
var activmenu = 0;
var cur = 0;
var tim;
var overactiv = 0;
var stored = '';

  v=parseInt(navigator.appVersion.substring(0,1));

  function load(location){
    image=new Image();
    image.src="img/m_"+location+".gif";
    return image;}

  if (v>=3){f1=load(1); f2=load(2);  f3=load(3); f4=load(4); f5=load(5);}

function showmenu(el,where,what) 
{if (dom) document.getElementById(el).style.visibility = "visible";
 else if (ie4) document.all[el].style.visibility = "visible";
 else if (nn4) document.layers[el].visibility = "show";
 activmenu = 1;

    if (v>=3){
      stored=where;
      storedLocation=document.images[where].src;
      document.images[where].src=eval(what+".src");}}

function hidemenu(el) 
{if (dom) document.getElementById(el).style.visibility = "hidden";
 else if (ie4) document.all[el].style.visibility = "hidden";
 else if (nn4) document.layers[el].visibility = "hide";
 hide();
 activmenu = 0;}

function hideall() 
{for (i=1; i<=maxmenu; i++)
 {
 if (dom) document.getElementById('menu'+i).style.visibility = "hidden";
 else if (ie4) document.all['menu'+i].style.visibility = "hidden";
 else if (nn4) document.layers['menu'+i].visibility = "hide";}
 activmenu = 0;}

function noactiv() 
{if (start != 0) hidemenu(cur)}

function activ(el,where,what) 
{if (activmenu == 1) 
{if (el != cur) {hidemenu(cur); showmenu(el,where,what); cur = el;}} 
   else {showmenu(el,where,what); cur = el;}}

function ClickActiv(where,what) 
{if (activmenu == 1) hidemenu(cur);
else showmenu(cur,where,what);}

function timeactiv()
{overactiv=0;
 tim=setTimeout('tactiv()','500');}

function tactiv()
{if (overactiv == 0 && activmenu == 1) hidemenu(cur);}

function timedisable()
{if (start != 0) 
{clearTimeout(tim);  overactiv=1}
else start = 1;}

  function hide(){
    if (v>=3) document.images[stored].src=storedLocation;}