Hey Julian ... I do this with a panel in xPages, and was having the same problem (getting it to show/hide properly and fadeIn on call ... here's what I ended up doing as a solution.

First, assign the div the class "startsHidden" ... here's the CSS definition for that class:

.startsHidden {

visibility: hidden;

}

then, add this code to your page:

dojo.addOnLoad(function(){

dojo.query(".startsHidden").style({ opacity:0 });

});

then, in your button to fadeIn() the object:

dojo.style("objectsId","visibility","visible");

dojo.fadeIn({node: "objectsId"}).play();

If you want to fade it back out, here is the code:

dojo.animateProperty({node: "objectId", properties: { opacity: 0 }, onEnd: function() { dojo.style("objectId","visibility","hidden");}}).play();

That works for me in both Firefox and at least IE7, havent tested IE8 yet....

Just a side note but related to IE's out of the box rendering capability... it's there, just exposed in a MS kind of way (read of course as "non standard" and "sucks"). You're on the trail with filter - but what you probably need to do for really good IE UI effects is start getting an understanding of DirectX. Even if you haven't installed the directX SDK, there are a lot of base effects that ship with Windows that IE can utilize. Proper alpha shading is one of these. Rather than dig through my own past exp with this, you'd be well served Googling a bit about the subject as no doubt, things have changed a bit since I last messed with this. Aside from what Jeremy posted above (not sure if you've had success with it in your situation or not), getting IE to do some of the things FF does easily will usually take some reinvention.

Jeremy, thanks for the tip. I thought of something similar but hoped for an easier solution.

I hate it do to extra code just for damn freaking IE :-(

Thanks for sharing your info. I really appreciate your efforts and I will be waiting for your further write ups thanks once again.