You can try some Javascript here.. *g*
Code:
<html>
<head>
<script type='text/javascript'>
var timer;
var opacity = 0;
function fadein()
{
opacity += 1;
document.body.style.opacity = opacity/10;
document.body.style.filter = 'alpha(opacity=' + opacity*10 + ')';
if(opacity == 10)
window.clearInterval(timer);
}
onload = new Function("timer = window.setInterval('fadein()',100);");
</script>
</head>
<body style='opacity:0; filter:alpha(opacity=0);'>
[BODY IN HERE]
</body>
</html>
See in action here:
http://projects.lucleonhart.de/fade.html
Works in all Browser i can test (FF, IE, Opera, Safari)