JavaScript - Get Ie Opacity

// configuration variables
var timeout   = 250; // milliseconds
var fadeSpeed = 500;  // milliseconds
var useFade   = true;

// timers array
var timers = new Array();

// state array -- by id, value = active, false = inactive
var state = new Array();

// lastOpacity: used to prevent multiple timers from making the fade flicker
var lastOpacity = new Array();

// MSIE has its own way of setting opacity, so we have to detect it
// all the other major browsers support the standard DOM opacity property
var msie = false;
if( navigator.appName == "Microsoft Internet Explorer" ) msie = true;

// entry point: set element to visible and clear its timers
function setMenu( id )
{
    var e = document.getElementById(id); //When the user rolls over one of horizontal menu items, the setMenu method is called and we pass in as an argument, the id of the associated ul element, which we then set its visibility attribute to visible.
    e.style.visibility = "visible";
    state[id] = true;
    setOpacity( id, 1 );
    if(timers[id]) {
        clearTimeout(timers[id]);
        timers[id] = undefined;
     }
}

// set element to hidden and reset its opacity
// typically called by a timer
// may be used as an entry point to bypass timers and fades
function hideMenu( id )
{
    var e = document.getElementById(id);
    state[id] = false;
    e.style.visibility = "hidden";
    if(useFade) setOpacity( id, 1 );
}

// entry point: hide the menu using fade (if enabled)
function clearMenu( id )
{
    if(useFade) timers[id] = setTimeout( 'fadeMenu( "' + id + '" )', timeout );
    else timers[id] = setTimeout( 'hideMenu( "' + id + '" )', timeout );
}

// set the opacity
// special support for MSIE
function setOpacity( id, value )
{
    var e = document.getElementById(id);

    if(state[id]) value = 1;    // menu fade was interrupted
    else if(lastOpacity[id] && (lastOpacity[id] < value)) value = lastOpacity[id];  // prevents flicker if multiple timers set
    
    if(msie) e.style.filter = 'alpha(opacity=' + value * 100 + ')'; // MS Internet Explorer
    else e.style.opacity = (value);     // Everyone else (standard DOM)

    if( value == 0 ) hideMenu( id );    // when all faded, reset the menu state
    lastOpacity[id] = value;
}

// fade a menu
// typically called by a timer
function fadeMenu ( id )
{
    var start = 0;
    var end = 0;
    var s = Math.round( fadeSpeed / 25 );   // fade in 25ms increments
    var timer = 0;
    var i;

    state[id] = false;

    for( i = s; i >= 0 ; i-- ) {
        setTimeout( "setOpacity('" + id + "'," + ( i / s ) + ")", timer++ * fadeSpeed / s )
    }
}

$(function () { 
	// Stack initialize
	var openspeed = 300;
	var closespeed = 300;
	$('.stack2>img').toggle(function(){
		var vertical = 0;
		var horizontal = 90;
		var $el=$(this);
		$el.next().children().each(function(){
			$(this).animate({top: vertical + 'px', left: horizontal + 'px', opacity: '10'}, openspeed);
			vertical = vertical + 40;
			horizontal = (horizontal+.75)*1.15;
		});
		$el.next().animate({top: '40px', left: '10px'}, openspeed).addClass('openStack')
		   .find('li a>img').animate({width: '50px', marginLeft: '9px'}, openspeed);
		$el.animate({paddingBottom: '0'});
	}, function(){
		//reverse above
		var $el=$(this);
		$el.next().removeClass('openStack').children('li').animate({top: '-33px', left: '-10px', opacity: '0'}, closespeed);
		$el.next().find('li a>img').animate({width: '79px', marginLeft: '0'}, closespeed);
		$el.animate({paddingBottom: '35px'});
	});
	
	// Stacks additional animation
	$('.stack2 li a').hover(function(){
		$("img",this).animate({width: '56px'}, 100);
		$("span",this).animate({marginRight: '30px'});
	},function(){
		$("img",this).animate({width: '50px'}, 100);
		$("span",this).animate({marginRight: '0'});
	});
});

/* ================ STACK #2 ================ */
.stack2 { position: fixed; top: 28px; left: 90px;}
.stack2 > img { position: relative; cursor: pointer; padding-bottom: 35px; z-index: 2; }
.stack2 ul { list-style: none; position: absolute; top: 7px; cursor: pointer; z-index: 1; }
.stack2 ul li { position: absolute;  }
.stack2 ul li img { border: 0;  }
.stack2 ul li span { display: none; }
.stack2 .openStack li span { 
	font-family: "Lucida Grande", Lucida, Verdana, sans-serif;
	display:block;
	height: 14px;
	position:absolute;
	top: 17px;
	right:60px;
	line-height: 14px;
	border: 0;
	background-color:#000;
	padding: 3px 10px;
	border-radius: 10px;
	-webkit-border-radius: 10px;
	-moz-border-radius: 10px;
	color: #fcfcfc;
	text-align: center;
	text-shadow: #000 1px 1px 1px;
	opacity: .85;
	filter: alpha(opacity = 85);
}

#dock { top: 0; left: 100px; }
a.dock-item { position: relative; float: left; margin-right: 10px; }
.dock-item span { display: block; }
.stack { top: 0; }
.stack ul li { position: relative; }

/* IE Fixes */
.stack2 { _position: absolute; }
.stack2 ul { _z-index:-1; _top:-15px; }
.stack2 ul li { *right:5px; }

<div class="stack2">
		<img src="images/stacks/stack-down.png" alt="stack"/>
		<ul id="stack2">
	    <li><a href=""><span>Aperture</span><img src="images/stacks/aperture.png" alt="Aperature" /></a></li>
			<li><a href="#"><span>All&nbsp;Examples</span><img src="images/stacks/photoshop.png" alt="Photoshop" /></a></li>
			<li><a href="example3.html"><span>Example&nbsp;3</span><img src="images/stacks/safari.png" alt="Safari" /></a></li>
			<li><a href="example2.html"><span>Example&nbsp;2</span><img src="images/stacks/coda.png" alt="Coda" /></a></li>
			<li><a href="index.html"><span>Example&nbsp;1</span><img src="images/stacks/finder.png" alt="Finder" /></a></li>			
		</ul>
</div>

<script>
document.getElementById("element").style.opacity="0";
</script>

<div id="element">
noopacity
</div>

div_opac = document.getElementById(some_div).style.opacity;