This is my javaScript for displaying a lightbox. It looks good in all browsers except for IE8, which puts a horizontal scrollbar at the bottom of the lightbox. I don't know javaScript very well, can someone help me with the code I need to add to this script to compensate for IE's problems?

Thanks!



/*
Created By: Chris Campbell
Website: http://particletree.com
Date: 2/1/2006

Inspired by the lightbox implementation found at http://www.huddletogether.com/projects/lightbox/
*/

/*-------------------------------GLOBAL VARIABLES------------------------------------*/

var detect = navigator.userAgent.toLowerCase();
var OS,browser,version,total,thestring;

/*-----------------------------------------------------------------------------------------------*/

//Browser detect script origionally created by Peter Paul Koch at http://www.quirksmode.org/

function getBrowserInfo() {
if (checkIt('konqueror')) {
browser = "Konqueror";
OS = "Linux";
}
else if (checkIt('safari')) browser = "Safari"
else if (checkIt('omniweb')) browser = "OmniWeb"
else if (checkIt('opera')) browser = "Opera"
else if (checkIt('webtv')) browser = "WebTV";
else if (checkIt('icab')) browser = "iCab"
else if (checkIt('msie')) browser = "Internet Explorer"
else if (!checkIt('compatible')) {
browser = "Netscape Navigator"
version = detect.charAt(8);
}
else browser = "An unknown browser";

if (!version) version = detect.charAt(place + thestring.length);

if (!OS) {
if (checkIt('linux')) OS = "Linux";
else if (checkIt('x11')) OS = "Unix";
else if (checkIt('mac')) OS = "Mac"
else if (checkIt('win')) OS = "Windows"
else OS = "an unknown operating system";
}
}

function checkIt(string) {
place = detect.indexOf(string) + 1;
thestring = string;
return place;
}

/*-----------------------------------------------------------------------------------------------*/

Event.observe(window, 'load', initialize, false);
Event.observe(window, 'load', getBrowserInfo, false);
Event.observe(window, 'unload', Event.unloadCache, false);

var lightbox = Class.create();

lightbox.prototype = {

yPos : 0,
xPos : 0,

initialize: function(ctrl) {
if ($('lbOnAuto')) {
var lbOnAuto = $('lbOnAuto').value;
if (lbOnAuto) {
this.content = lbOnAuto;
if (browser == 'Internet Explorer'){
this.getScroll();
this.prepareIE('2600px', 'scroll');
this.setScroll(0,0);
this.hideSelects('hidden');
}
this.displayLightbox("block");
$('lbOnAuto').value = '';
}
}

this.atag = ctrl;
this.content = ctrl.href;
Event.observe(ctrl, 'click', this.activate.bindAsEventListener(this), false);
ctrl.onclick = function(){
return false;
};
},

// Turn everything on - mainly the IE fixes
activate: function(){
if (browser == 'Internet Explorer'){
this.getScroll();
this.prepareIE('100%', 'hidden');
this.setScroll(0,0);
this.hideSelects('hidden');
}
this.displayLightbox("block");
},

// IE requires height to 100% and overflow hidden or else you can scroll down past the lightbox

prepareIE: function(height, overflow){
bod = document.getElementsByTagName('body')[0];
bod.style.height = height;
bod.style.overflow = overflow;

htm = document.getElementsByTagName('html')[0];
htm.style.height = height;
htm.style.overflow = overflow;
},

// In IE, select elements hover on top of the lightbox

hideSelects: function(visibility){
selects = document.getElementsByTagName('select');
for(i = 0; i < selects.length; i++) {
selects[i].style.visibility = visibility;
}
},


// Taken from lightbox implementation found at http://www.huddletogether.com/projects/lightbox/

getScroll: function(){
if (self.pageYOffset) {
this.yPos = self.pageYOffset;
} else if (document.documentElement && document.documentElement.scrollTop){
this.yPos = document.documentElement.scrollTop;
} else if (document.body) {
this.yPos = document.body.scrollTop;
}
},

setScroll: function(x, y){
window.scrollTo(x, y);
},

//
//
//
//
//
//
//
// Allow click on overlay to close lightbox

displayLightbox: function(display){

// if (browser == 'Internet Explorer') Event.observe(document, 'keydown', this.kHandler.bindAsEventListener(this), false); else Event.observe(document, 'keypress', this.kHandler.bindAsEventListener(this), false);
// $('overlay').onclick = this.deactivate.bindAsEventListener(this);
$('overlay').style.display = display;
$('lightbox').style.display = display;
if(display != 'none') this.loadInfo();
},


// Begin Ajax request based off of the href of the clicked linked

loadInfo: function() {
var myAjax = new Ajax.Request(
this.content,
{method: 'post', parameters: "", onComplete: this.processInfo.bindAsEventListener(this)}
);

},


// Display Ajax response

processInfo: function(response){
info = "<div id='lbContent'>" + response.responseText + "</div>";
new Insertion.Before($('lbLoadMessage'), info)
$('lightbox').className = "done";
this.actions();
},


// Search through new links within the lightbox, and attach click event

actions: function(){
lbActions = document.getElementsByClassName('lbAction');

for(i = 0; i < lbActions.length; i++) {
Event.observe(lbActions[i], 'click', this[lbActions[i].rel].bindAsEventListener(this), false);
lbActions[i].onclick = function(){return false;};
}
},

//
//
//
//
//
//
//
//
// The ability to exit using ESC

// kHandler: function(event){ switch(event.keyCode) { case Event.KEY_ESC: this.deactivate(); break; case Event.KEY_UP: case Event.KEY_DOWN: case Event.KEY_PAGEDOWN: case Event.KEY_PAGEUP: case Event.KEY_HOME: case Event.KEY_END: } },


// Example of creating your own functionality once lightbox is initiated

insert: function(e){
var pars = Form.serialize(Event.element(e).parentNode.id);
link = Event.element(e).parentNode;
Element.remove($('lbContent'));

var myAjax = new Ajax.Request(
link.href,
{method: 'post', parameters: pars, onComplete: this.processInfo.bindAsEventListener(this)}
);
},

// Example of creating your own functionality once lightbox is initiated

deactivate: function(){
if ($('lbContent')) Element.remove($('lbContent'));

if (browser == "Internet Explorer"){
this.setScroll(0,this.yPos);
this.prepareIE("auto", "auto");
this.hideSelects("visible");
}

this.displayLightbox("none");
}
}

/*-----------------------------------------------------------------------------------------------*/

// Onload, make all links that need to trigger a lightbox active

function initialize(){
addLightboxMarkup();
lbox = document.getElementsByClassName('lbOn');
for(i = 0; i < lbox.length; i++) {
valid = new lightbox(lbox[i]);
}
}

// Add in markup necessary to make this work. Basically two divs:
// Overlay holds the shadow
// Lightbox is the centered square that the content is put into.

function addLightboxMarkup() {
bod = document.getElementsByTagName('body')[0];
overlay = document.createElement('div');
overlay.id = 'overlay';
lb = document.createElement('div');
lb.id = 'lightbox';
lb.className = 'loading';
lb.innerHTML = '<div id="lbLoadMessage">' +
'<p>Loading</p>' +
'</div>';
bod.appendChild(overlay);
bod.appendChild(lb);
}