function na_hide_layers()
 {
  var i=0; mystuff="Stuff: ";
  x=document.getElementsByTagName("div")
  for (var i = 0; i < x.length-1; i++)
  {
   myElement = x[i].id;
   if (myElement.indexOf("layer") > 0) 
    { 
	 na_hide_layer(myElement);
	  }
   }
  }
 
function na_hide_layer(lname)
{
  if(document.getElementById) {
    document.getElementById(lname).style.visibility = 'hidden';
  } else if(document.layers) {
    document.layers[lname].visibility = 'hide'   
  } else if(document.all)
    document.all(lname).style.visibility = 'hidden' 
}

function na_preload_img()
{ 
  var img_list = na_preload_img.arguments;
  if (document.preloadlist == null) 
    document.preloadlist = new Array();
  var top = document.preloadlist.length;
  for (var i=0; i < img_list.length-1; i++) {
    document.preloadlist[top+i] = new Image;
    document.preloadlist[top+i].src = img_list[i+1];
  } 
}

function na_change_img_src(name, nsdoc, rpath, preload)
{ 
  var img = eval((navigator.appName.indexOf('Netscape', 0) != -1) ? nsdoc+'.'+name : 'document.all.'+name);
  if (name == '')
    return;
  if (img) {
    img.altsrc = img.src;
    img.src    = rpath;
  } 
}

function na_restore_img_src(name, nsdoc)
{
  var img = eval((navigator.appName.indexOf('Netscape', 0) != -1) ? nsdoc+'.'+name : 'document.all.'+name);
  if (name == '')
    return;
  if (img && img.altsrc) {
    img.src    = img.altsrc;
    img.altsrc = null;
  } 
}

function na_show_layer(lname)
{
  if (na_show_layer.arguments.length <= 1) { // don't delete, backword compatibility
    if(document.getElementById) {
      document.getElementById(lname).style.visibility = 'visible';
    } else if(document.layers) {
      document.layers[lname].visibility = 'show'   
    } else if(document.all)
      document.all(lname).style.visibility = 'visible' 
  } else {
    if(document.getElementById) {
      document.getElementById(lname).style.visibility = 'hidden';
    } else if(document.layers) {
      document.layers[lname].visibility = 'hide'   
    } else if(document.all)
      document.all(lname).style.visibility = 'hidden' 
  }
}