Asset.image will not load

[Matt Thomson]

Hi I am trying to get the asset.image for Mootools 1.11 working. I
need to stay with 1.11 until Joomla upgrades to mootools 1.2

These are the docs to asset functions:
http://docs111.mootools.net/Remote/Assets.js

My code is:
window.addEvent('domready', function()
{
        new Asset.image('myImage.gif', {
        onProgress: function(){
                alert('loading');
        },
        onComplete: function(){
                alert('complete');
        }
});

});

The code does nothing in IE and firefox, no errors either, has anyone
got this to work before?

Thanks,

Matt.