<!--
var visibleVar= "null";

browser_name = navigator.appName;
browser_version = parseFloat(navigator.appVersion); 

var roll="false";

function init(){
  if (browser_name == "Netscape") {
    layerStyleRef= "layer.";
	layerRef= "document.layers";
	styleSwitch= ".";
	visiblevar= "show";}  
    if (browser_version >= 3.0) {roll = 'false';}
    if (browser_version >= 4.0) {
      layerRef="document.getElementById";
      styleSwitch="style.";
    }
  else {
    layerStyleRef= "layer.style.";
    layerRef= "document.all";
    styleSwitch= "style.";
    visiblevar= "visible";
    if (browser_name == "Microsoft Internet Explorer" && browser_version >= 4.0) { roll = 'true'; }
  }
}
function showHideLayerSwitch(layerName){
  if (eval(layerRef+'["'+layerName+'"]'+styleSwitch+'visibility == visibleVar')){
    hideLayer(layerName);}
  else{
    showLayer(layerName);
  }
}
function showLayer(layerName){
  eval(layerRef+'("'+layerName+'").'+styleSwitch+'visibility = "visible"');
}
function hideLayer(layerName){
  eval(layerRef+'("'+layerName+'").'+styleSwitch+'visibility = "hidden"');
}
//initialize
init();

// -->