userAgent = window.navigator.userAgent;
browserVers = parseInt(userAgent.charAt(userAgent.indexOf("/")+1),10);
function newImage(arg) {
 if (document.images) {
  rslt = new Image();
  rslt.src = arg;
  return rslt;
 }
}

function findElement(n,ly) {
 if (browserVers < 4)		return document[n];
 var curDoc = ly ? ly.document : document;
 var elem = curDoc[n];
 if (!elem) {
  for (var i=0;i<curDoc.layers.length;i++) {
   elem = findElement(n,curDoc.layers[i]);
   if (elem) return elem;
  }
 }
 return elem;
}

function changeImages() {
 if (document.images && (preloadFlag == true)) {
  var img;
  for (var i=0; i<changeImages.arguments.length; i+=2) {
   img = null;
   if (document.layers) {
    img = findElement(changeImages.arguments[i],0);
   }
   else {
    img = document.images[changeImages.arguments[i]];
   }
   if (img) {
    img.src = changeImages.arguments[i+1];
   }
  }
 }
}

var preloadFlag = false;
function preloadImages() {
 if (document.images) {
  nav_03_over = newImage("img/nav/nav_03_over.gif");
  nav_04_over = newImage("img/nav/nav_04_over.gif");
  nav_05_over = newImage("img/nav/nav_05_over.gif");
  nav_06_over = newImage("img/nav/nav_06_over.gif");
  nav_07_over = newImage("img/nav/nav_07_over.gif");
  nav_08_over = newImage("img/nav/nav_08_over.gif");
  nav_12_nav_05_over = newImage("img/amgbmbh_over.gif");
  nav_13_nav_06_over = newImage("img/kbigmbh_over.gif");
  preloadFlag = true;
 }
}