A problem with a menu on my site

Hello,

This problem is truly baffling. On my site
(http://www.geekcenter.net/temp.html), I have a javascript menu. At the
bottom of the page is white space that is deleted when you place your mouse
over the link. To be quite honest, I have absolutely NO idea why this
happens. None whatsoever. I do, however, know that its cause lies in the
javascript file I've included below. If anyone could help, I'd greatly
appreciate it.

Thanks,
Kevin

----------------------------------------------

// Javascript File

var isDOM = (document.getElementById ? true : false);
var isIE4 = ((document.all && !isDOM) ? true : false);
var isNS4 = (document.layers ? true : false);

function getRef(id) {
if (isDOM) return document.getElementById(id);
if (isIE4) return document.all[id];
if (isNS4) return document.layers[id];
}

function getSty(id) {
return (isNS4 ? getRef(id) : getRef(id).style);
}

// Hide timeout.
var popTimer = 0;

// Array showing highlighted menu items.
var litNow = new Array();
function popOver(menuNum, itemNum) {
clearTimeout(popTimer);
hideAllBut(menuNum);
litNow = getTree(menuNum, itemNum);
changeCol(litNow, true);
targetNum = menu[menuNum][itemNum].targetmenu;
if (targetNum > 0) {
thisX = parseInt(menu[menuNum][0].ref.left) +
parseInt(menu[menuNum][itemNum].ref.left);
thisY = parseInt(menu[menuNum][0].ref.top) +
parseInt(menu[menuNum][itemNum].ref.top);
with (menu[targetNum][0].ref) {
left = parseInt(thisX + menu[targetNum][0].x);
top = parseInt(thisY + menu[targetNum][0].y);
visibility = 'visible';
}
}
}

function popOut(menuNum, itemNum) {
if ((menuNum == 0) && !menu[menuNum][itemNum].targetmenu)
hideAllBut(0)
else
popTimer = setTimeout('hideAllBut(0)', 500);
}

function getTree(menuNum, itemNum) {
// The array index is the menu number. Its contents are null (if the menu
is not a parent)
// or the item number of the menu that has kids (just so that we can light
it up)
itemArray = new Array(menu.length);

while(1) {
itemArray[menuNum] = itemNum;
// If we've reached the top of the hierarchy, return
if (menuNum == 0) return itemArray;
itemNum = menu[menuNum][0].parentItem;
menuNum = menu[menuNum][0].parentMenu;
}
}

// Pass an array and a boolean to specify color change, true = over color.
function changeCol(changeArray, isOver) {
for (menuCount = 0; menuCount < changeArray.length; menuCount++) {
if (changeArray[menuCount]) {
newCol = isOver ? menu[menuCount][0].overCol :
menu[menuCount][0].backCol;
// Change the colors of the div/layer background.
with (menu[menuCount][changeArray[menuCount]].ref) {
if (isNS4) bgColor = newCol;
else backgroundColor = newCol;
}
}
}
}

function hideAllBut(menuNum) {
var keepMenus = getTree(menuNum, 1);
for (count = 0; count < menu.length; count++) {
if (!keepMenus[count])
menu[count][0].ref.visibility = 'hidden';
changeCol(litNow, false);
}
}

function Menu(VerticalMenu, PopoutIcon, x, y, width, overCol, backCol,
borderClass, textClass) {
// True or false - a vertical menu or not
this.VerticalMenu = VerticalMenu;

// The popout icon used (if any) for this menu
this.PopoutIcon = PopoutIcon;

// Position and size settings.
this.x = x;
this.y = y;
this.width = width;

// Colors of menu and items.
this.overCol = overCol;
this.backCol = backCol;

// The stylesheet class used for item borders and the text within items.
this.borderClass = borderClass;
this.textClass = textClass;

// Parent menu and item numbers, indexed later.
this.parentMenu = null;
this.parentItem = null;

// Reference to the object's style properties (set later).
this.ref = null;
}

function Item(text, href, target, length, spacing, targetmenu) {
this.text = text;
this.href = href;
this.target = target;
this.length = length;
this.spacing = spacing;
this.targetmenu = targetmenu;

// Reference to the object's style properties (set later).
this.ref = null;
}

function writeMenu() {
if (!isDOM && !isIE4 && !isNS4) return;
for (currMenu = 0; currMenu < menu.length; currMenu++) with
(menu[currMenu][0]) {
// Variable for holding the HTML for items and the positions of the next
items.
var str = '', itemX = 0, itemY = 0;

// Items start from 1 in the array (0 is menu object).
// Also, they use properties of each item nested in the other with() for
construction.
for (currItem = 1; currItem < menu[currMenu].length; currItem++) with
(menu[currMenu][currItem]) {
var itemID = 'menu' + currMenu + 'item' + currItem;

// The width and height of the menu item depending on its orientation
var w = (VerticalMenu ? width : length);
var h = (VerticalMenu ? length : width);

// Create a div or layer text string with appropriate styles/properties.

if (isDOM || isIE4)
str += '<div id="' + itemID + '" style="position: absolute; left: ' +
itemX + '; top: ' + itemY + '; width: ' + w + '; height: ' + h + ';
visibility: inherit; background: #FFFFFF;"';

if (isNS4)
str += '<layer id="' + itemID + '" left="' + itemX + '" top="' + itemY +
'" width="' + w + '" height="' + h + '" visibility="inherit"
bgcolor="#FFFFFF"';

if (borderClass)
str += 'class="NormalBorder"';

// Add mouseover handlers and finish div/layer.
str += 'onMouseOver="popOver(' + currMenu + ',' + currItem + ')"
onMouseOut="popOut(' + currMenu + ',' + currItem + ')">';

// Add contents of item (default: table with link inside).
// In IE/NS6+, add padding if there's a border to emulate NS4's layer
padding.
// If a target frame is specified, also add that to the <a> tag.

str += '<table width="' + w + '" border="0" cellspacing="0"
cellpadding="0"><tr><td align="left" height="' + h + '"
onClick="window.location=\'' + href + '\';" style="cursor: hand"
valign="middle"><a class="' + textClass + '" href="' + href + '">' + text +
'</a></td>';

if (targetmenu > 0) {
// Set target's parents to this menu item.
menu[targetmenu][0].parentMenu = currMenu;
menu[targetmenu][0].parentItem = currItem;

// Add a popout indicator.
if (PopoutIcon)
str += '<td align="right">' + PopoutIcon + '</td>';
}

str += '</tr></table>' + (isNS4 ? '</layer>' : '</div>');

if (VerticalMenu)
itemY += length + spacing;
else
itemX += length + spacing;
}

if (isDOM) {
var newDiv = document.createElement('div');
document.getElementsByTagName('body').item(0).appe ndChild(newDiv);
newDiv.innerHTML = str;
ref = newDiv.style;
ref.position = 'absolute';
ref.visibility = 'hidden';
}

// Insert a div tag to the end of the body with menu HTML in place for
IE4.
if (isIE4) {
document.body.insertAdjacentHTML('beforeEnd', '<div id="menu' + currMenu
+ 'div" ' + 'style="position: absolute; visibility: hidden">' + str +
'</div>');
ref = getSty('menu' + currMenu + 'div');
}

// In NS4, create a reference to a new layer and write the items to it.
if (isNS4) {
ref = new Layer(0);
ref.document.write(str);
ref.document.close();
}

for (currItem = 1; currItem < menu[currMenu].length; currItem++) {
itemName = 'menu' + currMenu + 'item' + currItem;
if (isDOM || isIE4)
menu[currMenu][currItem].ref = getSty(itemName);
if (isNS4)
menu[currMenu][currItem].ref = ref.document[itemName];
}
}

with(menu[0][0]) {
ref.left = x;
ref.top = y;
ref.visibility = 'visible';
}
}