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) {
default_15_over = newImage("images/default_15_over.jpg");
default_16_over = newImage("images/default_16_over.jpg");
default_17_over = newImage("images/default_17_over.jpg");
default_18_over = newImage("images/default_18_over.jpg");
default_19_over = newImage("images/default_19_over.jpg");
preloadFlag = true;
}
}