Menu desplegable en HTML 5

Hola,
llevo varios años utilizando en HTML 4.0, un menú desplegable que nos brindó Jorgens hace ya mas de 4 años. Hasta ahora no había tenido problemas con él, pero al intentar utilizarlo en HTML 5 no consigo que me de el mismo resultado.
Los inconvenientes que me está causando en las paginas de prueba son un molesto espacio que no consigo hacer desaparecer, tanto en la parte superior como inferior del desplegable. Además, supongo que debido a ello, los sucesivos desplegables los va situando descuadrados con respecto al campo del que despliegan.

La diferencia entre ambos se puede ver en :

http://www.unaventanadesdemadrid.com/html5/prueba4.html (html 4.0)

http://www.unaventanadesdemadrid.com/html5/prueba5.html (html 5)

Código prueba5.html:

<!DOCTYPE html>
<html>
<header>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<link rel="stylesheet" href="estilo5.css" media="all" />
<link rel="stylesheet" href="estilo-menu-desplegable.css" media="all" />
<script language="javascript" src="TransmenuC.txt" ></script>
<script language="javascript" src="numero-de-menus.txt" ></script>
</header>
<body onload="init();">
<nav>
<ul>
<li><a id="desplegable1" href="#">Menú 1</a></li>
<li><a id="desplegable2" href="#">Menú 2</a></li>
<li><a id="desplegable3" href="#">Menú 3</a></li>
<li><a id="desplegable4" href="#">Menú 4</a></li>
</ul>
</nav>
<script language="javascript" src="definir-menus.txt" type="text/javascript"></script>
</body>
</html>

Código estilo5.css
nav {background-color: #B0C4DE; border-left: black 1px solid ; border-right: black 1px solid; border-top: black 1px solid;height:27px;}
nav li {float:left; list-style:none ; margin: 0px 0px 0px 26px;display:inline}
nav ul {display:inline;margin-left: 5px;}

Código estilo-menu-desplegable.css
/* <this is the clipping region for the menu. it's width and height get set by script, depending on the size of the items table */
.transMenu {
position:absolute;
overflow:hidden;
left:-1000px;
top:-1000px;
text-align: left;
}

/* this is the main container for the menu itself. it's width and height get set by script, depending on the size of the items table */
.transMenu .content {
position:absolute;
}

/* this table comprises all menu items. each TR is one item. It is relatively positioned so that the shadow and background transparent divs can be positioned underneath it */
.transMenu .items {
position:relative;
left:0px; top:0px;
border:1px solid #999;
z-index:2;
left:0px; top:0px;}

.transMenu.top .items {
border-top:none;
}

/* each TR.item is one menu item */
.transMenu .item {
color:#000000;
background-image: url(../objetos/fondo-no-activo.gif);
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: 9px;
font-weight: bold;
text-decoration:none;
/* this is a hack for mac/ie5, whom incorrectly cascades the border properties of the parent table to each row */
border:none;
cursor:pointer;}

/* this DIV is the semi-transparent white background of each menu. the -moz-opacity is a proprietary way to get transparency in mozilla, the filter is for IE/windows 5.0+. */
.transMenu .background {
position:absolute;
left:0px;
top:0px;
z-index:1;
-moz-opacity:0.8;
filter:alpha(opacity=95);
}

/* same concept as .background, but this is the sliver of shadow on the right of the menu. It's left, height, and background are set by script. In IE5/mac, it uses a PNG */
.transMenu .shadowRight {
position:absolute;
z-index:3;
top:3px; width:2px;
-moz-opacity:0.4;
filter:alpha(opacity=40);
}

/* same concept as .background, but this is the sliver of shadow on the bottom of the menu. It's top, width, and background are set by script. In IE5/mac, it uses a PNG */
.transMenu .shadowBottom {
position:absolute;
z-index:1;
left:3px; height:2px;
-moz-opacity:0.4;
filter:alpha(opacity=40);
}

/* this is the class that is used when the mouse is over an item. script sets the row to this class when required. */
.transMenu .item.hover {
background-image: url(../objetos/fondo-activo.gif);
color:#385385;
}

/* this is either the dingbat that indicates there is a submenu, or a spacer gif in it's place. We give it extra margin to create some space between the text and the dingbat */
.transMenu .item img {
margin-left:5px;
}
.textoNoIdent {
font-family: Arial, Helvetica, sans-serif;
font-size: 11px;
color: #333333;
text-decoration: none;
}
.formError {
font-family: Arial, Helvetica, sans-serif;
font-size: 12px;
font-weight: bold;
color: #333333;
border-top: 1px solid #C4CCCC;
border-right: 1px solid #ACB5B5;
border-bottom: 1px solid #6F7777;
border-left: 1px solid #ACB5B5;
padding: 2px 0 2px 0.25em;
background-color: #F5E984;
}
.txtError {
font-family: Arial, Helvetica, sans-serif;
font-size: 11px;
font-weight: bold;
color: #990000;
background-color: #E9E9E9;
padding: 5px;
text-align: justify;
}

Alguien me podría decir donde están fallando los códigos?

Podría utilizar otro menú desplegable para HTML 5 de los que van apareciendo por la red. El problema es aún no he encontrado ninguno que también disponga de un "Transmenu" que permita ir sumando paginas a la web sin tener que ir actualizando, con cada nueva página, los menus de cada página. En un caso como el nuestro, con más de 100 páginas, es algo demencial.


Gracias por la atención y perdón por la extensión de la consulta.
Códigos que no cabían en mensaje anterior (1 de 2):

Código TransmenuC.txt
* TransMenu
* March, 2003
*
* Customizable multi-level animated DHTML menus with transparency.
*
* Copyright 2003-2004, Aaron Boodman (www.youngpup.net)
* "Can I use this?"
*
* Use of this library is governed by the Creative Commons Attribution 2.0 License. You can check it
* out at: http://creativecommons.org/licenses/by/2.0/
*
* Basically: You may copy, distribute, and eat this code as you wish. But you must give me credit
* for writing it. You may not misrepresent yourself as the author of this code.
* "It's kinda hard to read, though"
*
* The uncompressed, commented version of this script can be found at:
* http://youngpup.net/projects/transMenus
* updates:
* 04.19.04 fixed cascade problem with menus nested greater than two levels.
* 12.23.03 added hideCurrent for menu actuators with no menus. renamed to TransMenu.
* 04.18.03 fixed render bug in IE 5.0 Mac by removing that browser from compatibility table ;)
* also made gecko check a little more strict by specifying build no.
// Configuration properties
TransMenu.spacerGif = "../objetos/espaciador.gif"; // path to a transparent spacer gif
TransMenu.dingbatOn = "../objetos/submenu-abierto.gif"; // path to the active sub menu dingbat
TransMenu.dingbatOff = "../objetos/submenu-cerrado.gif"; // path to the inactive sub menu dingbat
TransMenu.dingbatSize = 14000; // size of the dingbat (square shape assumed)
TransMenu.menuPadding = 0; // padding between menu border and items grid
TransMenu.itemPadding = 2; // additional padding around each item
TransMenu.shadowSize = 2; // size of shadow under menu
TransMenu.shadowOffset = 3; // distance shadow should be offset from leading edge
TransMenu.shadowColor = "#888"; // color of shadow (transparency is set in CSS)
TransMenu.shadowPng = "../objetos/gris.png"; // a PNG graphic to serve as the shadow for mac IE5
TransMenu.backgroundColor = "#C4CCCC"; // color of the background (transparency set in CSS)
TransMenu.backgroundPng = "../objetos/blanco.png"; // a PNG graphic to server as the background for mac IE5
TransMenu.hideDelay = 1000; // number of milliseconds to wait before hiding a menu
TransMenu.slideTime = 400; // number of milliseconds it takes to open and close a menu
TransMenu.preImg = "../objetos/punto.gif";

// Internal use properties
TransMenu.reference = {topLeft:1,topRight:2,bottomLeft:3,bottomRight:4};
TransMenu.direction = {down:1,right:2};
TransMenu.registry = [];
TransMenu._maxZ = 100;

// Static methods

// supporting win ie5+, mac ie5.1+ and gecko >= mozilla 1.0
TransMenu.isSupported = function() {
var ua = navigator.userAgent.toLowerCase();
var pf = navigator.platform.toLowerCase();
var an = navigator.appName;
var r = false;

if (ua.indexOf("gecko") > -1 && navigator.productSub >= 20020605) r = true; // gecko >= moz 1.0
else if (an == "Microsoft Internet Explorer") {
if (document.getElementById) { // ie5.1+ mac,win
if (pf.indexOf("mac") == 0) {
r = /msie (\d(.\d*)?)/.test(ua) && Number(RegExp.$1) >= 5.1;
}
else r = true;
}
}

return r;
}

// call this in onload once menus have been created
TransMenu.initialize = function() {
for (var i = 0, menu = null; menu = this.registry; i++) {
menu.initialize();
}
}

// call this in document body to write out menu html
TransMenu.renderAll = function() {
var aMenuHtml = [];
for (var i = 0, menu = null; menu = this.registry; i++) {
aMenuHtml = menu.toString();
}
document.write(aMenuHtml.join(""));
}

// TransMenu constructor (only called internally)
// oActuator : The thing that causes the menu to be shown when it is mousedover. Either a
// reference to an HTML element, or a TransMenuItem from an existing menu.
// iDirection : The direction to slide out. One of TransMenu.direction.
// iLeft : Left pixel offset of menu from actuator
// iTop : Top pixel offset of menu from actuator
// iReferencePoint : Corner of actuator to measure from. One of TransMenu.referencePoint.
// parentMenuSet : Menuset this menu will be added to.
function TransMenu(oActuator, iDirection, iLeft, iTop, iReferencePoint, parentMenuSet) {
// public methods
this.addItem = addItem;
this.addMenu = addMenu;
this.toString = toString;
this.initialize = initialize;
this.isOpen = false;
this.show = show;
this.hide = hide;
this.items = [];

// events
this.onactivate = new Function(); // when the menu starts to slide open
this.ondeactivate = new Function(); // when the menu finishes sliding closed
this.onmouseover = new Function(); // when the menu has been moused over
this.onqueue = new Function(); // hack .. when the menu sets a timer to be closed a little while in the future
this.ondequeue = new Function();

// initialization
this.index = TransMenu.registry.length;
TransMenu.registry[this.index] = this;

var id = "TransMenu" + this.index;
var contentHeight = null;
var contentWidth = null;
var childMenuSet = null;
var animating = false;
var childMenus = [];
var slideAccel = -1;
var elmCache = null;
var ready = false;
var _this = this;
var a = null;

var pos = iDirection == TransMenu.direction.down ? "top" : "left";
var dim = null;

// private and public method implimentations
function addItem(sText, sUrl) {
var item = new TransMenuItem(sText, sUrl, this);
item._index = this.items.length;
this.items[item._index] = item;
}

function addMenu(oMenuItem) {
if (!oMenuItem.parentMenu == this) throw new Error("Cannot add a menu here");

if (childMenuSet == null) childMenuSet = new TransMenuSet(TransMenu.direction.right, -5, 2, TransMenu.reference.topRight);

var m = childMenuSet.addMenu(oMenuItem);

childMenus[oMenuItem._index] = m;
m.onmouseover = child_mouseover;
m.ondeactivate = child_deactivate;
m.onqueue = child_queue;
m.ondequeue = child_dequeue;

return m;
}

function initialize() {
initCache();
initEvents();
initSize();
ready = true;
}

function show() {
//dbg_dump("show");
if (ready) {
_this.isOpen = true;
animating = true;
setContainerPos();
elmCache["clip"].style.visibility = "visible";
elmCache["clip"].style.zIndex = TransMenu._maxZ++;
//dbg_dump("maxZ: " + TransMenu._maxZ);
slideStart();
_this.onactivate();
}
}

function hide() {
if (ready) {
_this.isOpen = false;
animating = true;

for (var i = 0, item = null; item = elmCache.item; i++)
dehighlight(item);

if (childMenuSet) childMenuSet.hide();

slideStart();
_this.ondeactivate();
}
}

function setContainerPos() {
var sub = oActuator.constructor == TransMenuItem;
var act = sub ? oActuator.parentMenu.elmCache["item"][oActuator._index] : oActuator;
var el = act;

var x = 0;
var y = 0;


var minX = 0;
var maxX = (window.innerWidth ? window.innerWidth : document.body.clientWidth) - parseInt(elmCache["clip"].style.width);
var minY = 0;
var maxY = (window.innerHeight ? window.innerHeight : document.body.clientHeight) - parseInt(elmCache["clip"].style.height);

// add up all offsets... subtract any scroll offset
while (sub ? el.parentNode.className.indexOf("transMenu") == -1 : el.offsetParent) {
x += el.offsetLeft;
y += el.offsetTop;

if (el.scrollLeft) x -= el.scrollLeft;
if (el.scrollTop) y -= el.scrollTop;

el = el.offsetParent;
}

if (oActuator.constructor == TransMenuItem) {
x += parseInt(el.parentNode.style.left);
y += parseInt(el.parentNode.style.top);
}

switch (iReferencePoint) {
case TransMenu.reference.topLeft:
break;
case TransMenu.reference.topRight:
x += act.offsetWidth;
break;
case TransMenu.reference.bottomLeft:
y += act.offsetHeight;
break;
case TransMenu.reference.bottomRight:
x += act.offsetWidth;
y += act.offsetHeight;
break;
}

x += iLeft;
y += iTop;

x = Math.max(Math.min(x, maxX), minX);
y = Math.max(Math.min(y, maxY), minY);

elmCache["clip"].style.left = x + "px";
elmCache["clip"].style.top = y + "px";
}

function slideStart() {
var x0 = parseInt(elmCache["content"].style);
var x1 = _this.isOpen ? 0 : -dim;

if (a != null) a.stop();
a = new Accelimation(x0, x1, TransMenu.slideTime, slideAccel);

a.onframe = slideFrame;
a.onend = slideEnd;

a.start();
}

function slideFrame(x) {
elmCache["content"].style = x + "px";
}

function slideEnd() {
if (!_this.isOpen) elmCache["clip"].style.visibility = "hidden";
animating = false;
}

function initSize() {
// everything is based off the size of the items table...
var ow = elmCache["items"].offsetWidth;
var oh = elmCache["items"].offsetHeight;
var ua = navigator.userAgent.toLowerCase();

// clipping container should be ow/oh + the size of the shadow
elmCache["clip"].style.width = ow + TransMenu.shadowSize + 2 + "px";
elmCache["clip"].style.height = oh + TransMenu.shadowSize + 2 + "px";

// same with content...
elmCache["content"].style.width = ow + TransMenu.shadowSize + "px";
elmCache["content"].style.height = oh + TransMenu.shadowSize + "px";

contentHeight = oh + TransMenu.shadowSize;
contentWidth = ow + TransMenu.shadowSize;

dim = iDirection == TransMenu.direction.down ? contentHeight : contentWidth;

// set initially closed
elmCache["content"].style = -dim - TransMenu.shadowSize + "px";
elmCache["clip"].style.visibility = "hidden";

// if *not* mac/ie 5
if (ua.indexOf("mac") == -1 || ua.indexOf("gecko") > -1) {
// set background div to offset size
elmCache["background"].style.width = ow + "px";
elmCache["background"].style.height = oh + "px";
elmCache["background"].style.backgroundColor = TransMenu.backgroundColor;

// shadow left starts at offset left and is offsetHeight pixels high
elmCache["shadowRight"].style.left = ow + "px";
elmCache["shadowRight"].style.height = oh - (TransMenu.shadowOffset - TransMenu.shadowSize) + "px";
elmCache["shadowRight"].style.backgroundColor = TransMenu.shadowColor;

// shadow bottom starts at offset height and is offsetWidth - shadowOffset
// pixels wide (we don't want the bottom and right shadows to overlap or we
// get an extra bright bottom-right corner)
elmCache["shadowBottom"].style.top = oh + "px";
elmCache["shadowBottom"].style.width = ow - TransMenu.shadowOffset + "px";
elmCache["shadowBottom"].style.backgroundColor = TransMenu.shadowColor;
}
// mac ie is a little different because we use a PNG for the transparency
else {
// set background div to offset size
elmCache["background"].firstChild.src = TransMenu.backgroundPng;
elmCache["background"].firstChild.width = ow;
elmCache["background"].firstChild.height = oh;

// shadow left starts at offset left and is offsetHeight pixels high
elmCache["shadowRight"].firstChild.src = TransMenu.shadowPng;
elmCache["shadowRight"].style.left = ow + "px";
elmCache["shadowRight"].firstChild.width = TransMenu.shadowSize;
elmCache["shadowRight"].firstChild.height = oh - (TransMenu.shadowOffset - TransMenu.shadowSize);

// shadow bottom starts at offset height and is offsetWidth - shadowOffset
// pixels wide (we don't want the bottom and right shadows to overlap or we
// get an extra bright bottom-right corner)
elmCache["shadowBottom"].firstChild.src = TransMenu.shadowPng;
elmCache["shadowBottom"].style.top = oh + "px";
elmCache["shadowBottom"].firstChild.height = TransMenu.shadowSize;
elmCache["shadowBottom"].firstChild.width = ow - TransMenu.shadowOffset;
}
}

function initCache() {
var menu = document.getElementById(id);
var all = menu.all ? menu.all : menu.getElementsByTagName("*"); // IE/win doesn't support * syntax, but does have the document.all thing

elmCache = {};
elmCache["clip"] = menu;
elmCache["item"] = [];

for (var i = 0, elm = null; elm = all; i++) {
switch (elm.className) {
case "items":
case "content":
case "background":
case "shadowRight":
case "shadowBottom":
elmCache[elm.className] = elm;
break;
case "item":
elm._index = elmCache["item"].length;
elmCache["item"][elm._index] = elm;
break;
}
}

// hack!
_this.elmCache = elmCache;
}

function initEvents() {
// hook item mouseover
for (var i = 0, item = null; item = elmCache.item; i++) {
item.onmouseover = item_mouseover;
item.onmouseout = item_mouseout;
item.onclick = item_click;
}

// hook actuation
if (typeof oActuator.tagName != "undefined") {
oActuator.onmouseover = actuator_mouseover;
oActuator.onmouseout = actuator_mouseout;
}

// hook menu mouseover
elmCache["content"].onmouseover = content_mouseover;
elmCache["content"].onmouseout = content_mouseout;
}

function highlight(oRow) {
oRow.className = "item hover";
if (childMenus[oRow._index])
oRow.lastChild.firstChild.src = TransMenu.dingbatOn;
}

function dehighlight(oRow) {
oRow.className = "item";
if (childMenus[oRow._index])
oRow.lastChild.firstChild.src = TransMenu.dingbatOff;
}

function item_mouseover() {
if (!animating) {
highlight(this);

if (childMenus[this._index])
childMenuSet.showMenu(childMenus[this._index]);
else if (childMenuSet) childMenuSet.hide();
}
}

function item_mouseout() {
if (!animating) {
if (childMenus[this._index])
childMenuSet.hideMenu(childMenus[this._index]);
else // otherwise child_deactivate will do this
dehighlight(this);
}
}

function item_click() {
if (!animating) {
if (_this.items[this._index].url)
location.href = _this.items[this._index].url;
}
}

function actuator_mouseover() {
parentMenuSet.showMenu(_this);
}

function actuator_mouseout() {
parentMenuSet.hideMenu(_this);
}

function content_mouseover() {
if (!animating) {
parentMenuSet.showMenu(_this);
_this.onmouseover();
}
}

function content_mouseout() {
if (!animating) {
parentMenuSet.hideMenu(_this);
}
}

function child_mouseover() {
if (!animating) {
parentMenuSet.showMenu(_this);
}
}

function child_deactivate() {
for (var i = 0; i < childMenus.length; i++) {
if (childMenus == this) {
dehighlight(elmCache["item"]);
break;
}
}
}

function child_queue() {
parentMenuSet.hideMenu(_this);
}

function child_dequeue() {
parentMenuSet.showMenu(_this);
}

function toString() {
var aHtml = [];
var sClassName = "transMenu" + (oActuator.constructor != TransMenuItem ? " top" : "");

for (var i = 0, item = null; item = this.items; i++) {
aHtml = item.toString(childMenus);
}

return '<div id="' + id + '" class="' + sClassName + '">' +
'<div class="content"><table class="items" cellpadding="0" cellspacing="0" border="0">' +
'<tr><td colspan="2"><img src="' + TransMenu.spacerGif + '" width="1" height="' + TransMenu.menuPadding + '"></td></tr>' +
aHtml.join('') +
'<tr><td colspan="2"><img src="' + TransMenu.spacerGif + '" width="1" height="' + TransMenu.menuPadding + '"></td></tr></table>' +
'<div class="shadowBottom"><img src="' + TransMenu.spacerGif + '" width="1" height="1"></div>' +
'<div class="shadowRight"><img src="' + TransMenu.spacerGif + '" width="1" height="1"></div>' +
'<div class="background"><img src="' + TransMenu.spacerGif + '" width="1" height="1"></div>' +
'</div></div>';
}
}


//==================================================================================================
// TransMenuSet
//==================================================================================================
// iDirection : The direction to slide out. One of TransMenu.direction.
// iLeft : Left pixel offset of menus from actuator
// iTop : Top pixel offset of menus from actuator
// iReferencePoint : Corner of actuator to measure from. One of TransMenu.referencePoint.
//==================================================================================================
TransMenuSet.registry = [];

function TransMenuSet(iDirection, iLeft, iTop, iReferencePoint) {
// public methods
this.addMenu = addMenu;
this.showMenu = showMenu;
this.hideMenu = hideMenu;
this.hide = hide;
this.hideCurrent = hideCurrent;

// initialization
var menus = [];
var _this = this;
var current = null;

this.index = TransMenuSet.registry.length;
TransMenuSet.registry[this.index] = this;

// method implimentations...
function addMenu(oActuator) {
var m = new TransMenu(oActuator, iDirection, iLeft, iTop, iReferencePoint, this);
menus[menus.length] = m;
return m;
}

function showMenu(oMenu) {
if (oMenu != current) {
// close currently open menu
if (current != null) hide(current);

// set current menu to this one
current = oMenu;

// if this menu is closed, open it
oMenu.show();
}
else {
// hide pending calls to close this menu
cancelHide(oMenu);
}
}

function hideMenu(oMenu) {
//dbg_dump("hideMenu a " + oMenu.index);
if (current == oMenu && oMenu.isOpen) {
//dbg_dump("hideMenu b " + oMenu.index);
if (!oMenu.hideTimer) scheduleHide(oMenu);
}
}

function scheduleHide(oMenu) {
//dbg_dump("scheduleHide " + oMenu.index);
oMenu.onqueue();
oMenu.hideTimer = window.setTimeout("TransMenuSet.registry[" + _this.index + "].hide(TransMenu.registry[" + oMenu.index + "])", TransMenu.hideDelay);
}

function cancelHide(oMenu) {
//dbg_dump("cancelHide " + oMenu.index);
if (oMenu.hideTimer) {
oMenu.ondequeue();
window.clearTimeout(oMenu.hideTimer);
oMenu.hideTimer = null;
}
}

function hide(oMenu) {
if (!oMenu && current) oMenu = current;

if (oMenu && current == oMenu && oMenu.isOpen) {
hideCurrent();
}
}

function hideCurrent() {
if (null != current) {
cancelHide(current);
current.hideTimer = null;
current.hide();
current = null;
}
}
}

//==================================================================================================
// TransMenuItem (internal)
// represents an item in a dropdown
//==================================================================================================
// sText : The item display text
// sUrl : URL to load when the item is clicked
// oParent : Menu this item is a part of
//==================================================================================================
function TransMenuItem(sText, sUrl, oParent) {
this.toString = toString;
this.text = sText;
this.url = sUrl;
this.parentMenu = oParent;

function toString(bDingbat) {
var sDingbat = bDingbat ? TransMenu.dingbatOff : TransMenu.spacerGif;
var iEdgePadding = TransMenu.itemPadding + TransMenu.menuPadding;
var sPaddingLeft = "padding:" + TransMenu.itemPadding + "px; padding-left:" + iEdgePadding + "px;"
var sPaddingRight = "padding:" + TransMenu.itemPadding + "px; padding-right:" + iEdgePadding + "px;"

return '<tr class="item" ><td width="16" style="' + sPaddingLeft + '" >' + '<img src="'+TransMenu.preImg+'" border="0" width="0" height="0"></td><td nowrap style="' + sPaddingLeft + '" >' +
sText + '</td><td width="14" style="' + sPaddingRight + '" >' +
'<img src="' + sDingbat + '" width="14" height="14"></td></tr>';
}
}

//=====================================================================
// Accel imation object
// change a property of an object over time in an accelerated fashion
//=====================================================================
// obj : reference to the object whose property you'd like to animate
// prop : property you would like to change eg: "left"
// to : final value of prop
// time : time the animation should take to run
// zip : optional. specify the zippiness of the acceleration. pick a
// number between -1 and 1 where -1 is full decelerated, 1 is
// full accelerated, and 0 is linear (no acceleration). default
// is 0.
// unit : optional. specify the units for use with prop. default is
// "px".

// bezier functions lifted from the lib_animation.js file in the
// 13th Parallel API. www.13thparallel.org


function Accelimation(from, to, time, zip) {
if (typeof zip == "undefined") zip = 0;
if (typeof unit == "undefined") unit = "px";

this.x0 = from;
this.x1 = to;
this.dt = time;
this.zip = -zip;
this.unit = unit;
this.timer = null;
this.onend = new Function();
this.onframe = new Function();
}

// public methods


// after you create an accelimation, you call this to start it-a runnin'
Accelimation.prototype.start = function() {
this.t0 = new Date().getTime();
this.t1 = this.t0 + this.dt;
var dx = this.x1 - this.x0;
this.c1 = this.x0 + ((1 + this.zip) * dx / 3);
this.c2 = this.x0 + ((2 + this.zip) * dx / 3);
Accelimation._add(this);
}

// and if you need to stop it early for some reason...
Accelimation.prototype.stop = function() {
Accelimation._remove(this);
}


// private methods


// paints one frame. gets called by Accelimation._paintAll.
Accelimation.prototype._paint = function(time) {
if (time < this.t1) {
var elapsed = time - this.t0;
this.onframe(Accelimation._getBezier(elapsed/this.dt,this.x0,this.x1,this.c1,this.c2));
}
else this._end();
}

// ends the animation
Accelimation.prototype._end = function() {
Accelimation._remove(this);
this.onframe(this.x1);
this.onend();
}


// static methods (all private)


// add a function to the list of ones to call periodically
Accelimation._add = function(o) {
var index = this.instances.length;
this.instances = o;
// if this is the first one, start the engine
if (this.instances.length == 1) {
this.timerID = window.setInterval("Accelimation._paintAll()", this.targetRes);
}
}

// remove a function from the list
Accelimation._remove = function(o) {
for (var i = 0; i < this.instances.length; i++) {
if (o == this.instances) {
this.instances = this.instances.slice(0,i).concat( this.instances.slice(i+1) );
break;
}
}
// if that was the last one, stop the engine
if (this.instances.length == 0) {
window.clearInterval(this.timerID);
this.timerID = null;
}
}

// "engine" - call each function in the list every so often
Accelimation._paintAll = function() {
var now = new Date().getTime();
for (var i = 0; i < this.instances.length; i++) {
this.instances._paint(now);
}
}


// Bezier functions:
Accelimation._B1 = function(t) { return t*t*t }
Accelimation._B2 = function(t) { return 3*t*t*(1-t) }
Accelimation._B3 = function(t) { return 3*t*(1-t)*(1-t) }
Accelimation._B4 = function(t) { return (1-t)*(1-t)*(1-t) }


//Finds the coordinates of a point at a certain stage through a bezier curve
Accelimation._getBezier = function(percent,startPos,endPos,control1,control2) {
return endPos * this._B1(percent) + control2 * this._B2(percent) + control1 * this._B3(percent) + startPos * this._B4(percent);
}


// static properties

Accelimation.instances = [];
Accelimation.targetRes = 10;
Accelimation.timerID = null;


// IE win memory cleanup

if (window.attachEvent) {
var cearElementProps = [
'data',
'onmouseover',
'onmouseout',
'onmousedown',
'onmouseup',
'ondblclick',
'onclick',
'onselectstart',
'oncontextmenu'
];

window.attachEvent("onunload", function() {
var el;
for(var d = document.all.length;d--;){
el = document.all;
for(var c = cearElementProps.length;c--;){
el[cearElementProps] = null;
}
}
});
}
Código que no cabe en mensaje inicial (2de2)

Código de numero-de-menus.txt
function init()
{
if (TransMenu.isSupported())
{
TransMenu.initialize();
desplegable1.onactivate=function(){document.getElementById('desplegable1').className = 'hover';};
desplegable1.ondeactivate=function(){document.getElementById('desplegable1').className = ''; }
desplegable2.onactivate=function(){document.getElementById('desplegable2').className = 'hover'; };
desplegable2.ondeactivate=function(){document.getElementById('desplegable2').className = ''; }
desplegable3.onactivate=function(){document.getElementById('desplegable3').className = 'hover'; };
desplegable3.ondeactivate=function(){document.getElementById('desplegable3').className = ''; }
desplegable4.onactivate=function(){document.getElementById('desplegable4').className = 'hover'; };
desplegable4.ondeactivate=function(){document.getElementById('desplegable4').className = ''; }
}
}

Código de definir-menus.txt
if (TransMenu.isSupported())
{
var ms=new TransMenuSet(TransMenu.direction.down,1,0, TransMenu.reference.bottomLeft);

var desplegable1 = ms.addMenu(document.getElementById('desplegable1'));
desplegable1.addItem('Subnivel 1.1','');
var desplegable1_0 = desplegable1.addMenu(desplegable1.items[0])
desplegable1_0.addItem('Subnivel 1.1.1','../111.html');
desplegable1.addItem('Subnivel 1.2','../12.html');

var desplegable2 = ms.addMenu(document.getElementById('desplegable2'));
desplegable2.addItem('Subnivel 2.1','../12.html');

var desplegable3 = ms.addMenu(document.getElementById('desplegable3'));
desplegable3.addItem('Subnivel 3.1','../12.html');
var desplegable4 = ms.addMenu(document.getElementById('desplegable4'));
desplegable4.addItem('Subnivel 4.1','../12.html');
TransMenu.renderAll();
}
Modificados los códigos. De momento funciona en Chrome, Mozilla Firefox, Opera, ie8 y 9. Copio los códigos cuando pruebe en Safari y consiga que funcione en ie7
Hola:

Para no tener que partir el código en 2, utiliza las etiquetas
o
.

Saludos.
Lamento el retraso, aquí esta el código, en dos semanas los quitaré de mi espacio web.

html5.html

<!DOCTYPE html>
 <html lang="es">
 <header>
<meta charset="utf-8" /> 
<header>
			<link rel="stylesheet" href="estilo5.css" type="text/css" media="all">
			<link rel="stylesheet" href="estilo-menu-desplegable.css" type="text/css" media="all">
			<script language="javascript" src="transmenu.js" type="text/javascript"/></script> 
			<script language="javascript" src="numero-de-menus.txt" type="text/javascript"></script>
			<script src="script/jquery-1.6.2.min.js" type="text/javascript"></script>
			</script>
			
			
</header>
<body onload="init();">

<nav>
  <div id="navegacion">
          <ul>
  						<li><a id="desplegable1" href="#">Menú 1</a></li>
  						<li><a id="desplegable2" href="#">Menú 2</a></li>
  						<li><a id="desplegable3" href="#">Menú 3</a></li>
  						<li><a id="desplegable4" href="#">Menú 4</a></li>
        	</ul>
  				<script language="javascript" src="definir-menus.txt" type="text/javascript"></script>
  </div>
<hgroup>

</hgroup>
</nav>
<section>
<br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/><br/>
</section>	

<footer>
</footer>
</body>
</html>

estilo5.css

/* Cabecera */
#cabecera {background-color: white; height:110px;}
/* Navegación */
#navegacion {background-color: #B0C4DE; height:30px; }
#navegacion li {float:left; list-style:none ; margin: 0px 0px 0px 26px;display:inline}
#navegacion ul {display:inline; margin-left: 5px; }
h1 {border-left: #4682B4 5px solid ; border-right: #4682B4 5px solid ; font-size: 1.5em; background-color: #000080; color:#FFFFFF ; font-weight: bold ;text-align:center;margin:0;padding:2px 0 2px 0;}
h2 {border-left: #4682B4 5px solid ; border-right: #4682B4 5px solid ; font-size: 1.1em; background-color: #4682B4; color:#FFFFFF ; font-weight: bold ;text-align:center;margin:0;padding:2px 0 2px 0;}

/* Enlaces */
a {color: #0000FF; text-decoration: none; display: inline}
a:link {}
a:visited {}
a:hover {color:#ADD8E6; text-decoration:underline; background-color: #E6E6FA}
a:active {color:red; display: inline}

estilo-menu-desplegable.css

 
/* <this is the clipping region for the menu. it's width and height get set by script, depending on the size of the items table */
/* <esta es la región de recorte para el menú. es obtener la anchura y la altura fijado por la escritura, dependiendo del tamaño de los artículos de mesa*/
.transMenu {
	position:absolute;
	margin:0px;
	overflow:hidden;
	left:-1000px;
	top:-1000px;
	text-align: left;
	}

/* this is the main container for the menu itself. it's width and height get set by script, depending on the size of the items table */
/* este es el principal contenedor para el menú. es obtener la anchura y la altura fijado por la escritura, dependiendo del tamaño de los artículos de mesa */
.transMenu .content {
	position:absolute;
	}

/* this table comprises all menu items. each TR is one item. It is relatively positioned so that the shadow and background transparent divs can be positioned underneath it */
/* este cuadro incluye todos los elementos de menú. cada TR es un tema. Es relativamente colocarse de tal forma que la sombra y el fondo transparente divs se puede colocar debajo de ella */
.transMenu .items {
	position:relative;
	padding:0px;				 
  border-collapse:collapse;
	border-spacing: 0px;
	z-index:2;
	left:0px; top:-20px;
	}

.transMenu.top .items {
	border-top:none;
	}

/* each TR.item is one menu item */
/* cada TR.item es un elemento de menú */
.transMenu .item {
	 color:navy;
  background-image: url(http://www.unaventanadesdemadrid.com/objetos/mantenimiento/white-90.png);
	font-family: Verdana, Arial, Helvetica, sans-serif;
	font-size: 9px;
	font-weight: bold;
    text-decoration:none;
	/* this is a hack for mac/ie5, whom incorrectly cascades the border properties of the parent table to each row */
	/* este es un truco para mac/ie5, a quien erróneamente las cascadas de la frontera propiedades de la tabla padre para cada fila */
	border:none;
	cursor:pointer;}

/* this DIV is the semi-transparent white background of each menu. the -moz-opacity is a proprietary way to get transparency in mozilla, the filter is for IE/windows 5.0+. */
/* we set the background color in script because ie mac does not use it; that browser only uses a semi-transparent white PNG that the spacer gif inside this DIV is replaced by */
.transMenu .background {
	position:absolute;
	left:0px;
	top:0px;
	z-index:0;
	-moz-opacity:0.8;
	filter:alpha(opacity=95);
	}

/* same concept as .background, but this is the sliver of shadow on the right of the menu. It's left, height, and background are set by script. In IE5/mac, it uses a PNG */
.transMenu .shadowRight {
	position:absolute;
	z-index:0;
	top:0px; width:0px;
	-moz-opacity:0.4;
	filter:alpha(opacity=40);
	}

/* same concept as .background, but this is the sliver of shadow on the bottom of the menu. It's top, width, and background are set by script. In IE5/mac, it uses a PNG */
.transMenu .shadowBottom {
	position:absolute;
	z-index:0;
	left:0px; height:0px;
	-moz-opacity:0.4;
	filter:alpha(opacity=40);
	}

/* this is the class that is used when the mouse is over an item. script sets the row to this class when required. */
.transMenu .item.hover {
	background-image: url(http://www.unaventanadesdemadrid.com/objetos/mantenimiento/fondo-activo.gif);
	color:#385385;
	}

/* this is either the dingbat that indicates there is a submenu, or a spacer gif in it's place. We give it extra margin to create some space between the text and the dingbat */
.transMenu .item img {
	margin-left:0px;
	}
.textoNoIdent {
	font-family: Arial, Helvetica, sans-serif;
	font-size: 11px;
	color: #333333;
	text-decoration: none;
}
.formError {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 12px;
    font-weight: bold;
    color: #333333;
    border-top: 0px solid #C4CCCC;
    border-right: 0px solid #ACB5B5;
    border-bottom: 0px solid #6F7777;
    border-left: 0px solid #ACB5B5;
    padding: 0px;
    background-color: #F5E984;
}
.txtError {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 11px;
    font-weight: bold;
    color: #990000;
    background-color: #E9E9E9;
    padding: 0px;
    text-align: justify;
}

numero-de-menus.txt

function init()
{
if (TransMenu.isSupported()) 
  {
TransMenu.initialize();
desplegable1.onactivate=function(){document.getElementById('desplegable1').className = 'hover';};
desplegable1.ondeactivate=function(){document.getElementById('desplegable1').className = ''; };
desplegable2.onactivate=function(){document.getElementById('desplegable2').className = 'hover'; };
desplegable2.ondeactivate=function(){document.getElementById('desplegable2').className = ''; };
desplegable3.onactivate=function(){document.getElementById('desplegable3').className = 'hover'; };
desplegable3.ondeactivate=function(){document.getElementById('desplegable3').className = ''; };
desplegable4.onactivate=function(){document.getElementById('desplegable4').className = 'hover'; };
desplegable4.ondeactivate=function(){document.getElementById('desplegable4').className = ''; };
  }
}