animate transparency (opacity) in IE8

animate transparency (opacity) in IE8

Hi All
I want to change the opacity of a 'div' from its initial opacity/state
to an other using jQuery's animate function. Here is my test html file
<html>
<head>
<script>
$(document).ready(function(){
$("#xyz").animate({ opacity: '1'}, 5000) ;
});
</script>
<style>
.lessvisible {
-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=50)";
filter: alpha(opacity=50);
-khtml-opacity: 0.5;
-moz-opacity: 0.5;
opacity: 0.5;
}
</style>
</head>
<body>
<div id="xyz" class="lessvisible">
Lorem ipsum dolor sit amet, consectetur adipisicing elit, ......
</div>
<div>aaaaaaa</div>
</body>
</html>
In my IE8 browser I don't see any animation but only the end result,
as if the duration is set to 0 seconds.
(I've tested it in IE6 and IE7 which didn't show me any transparency/
animation at all)
Any suggestions ?
thnx
LuCa
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