var map = {

init: function(){
  var img = $$('.commissionimg img')[1];
  var div = $$('.commissionimg')[0];
  img.setOpacity(0);
  div.addEvent('mouseover', function(){img.fade('in');} );
  div.addEvent('mouseout', function(){img.fade('out');} );
}

}

window.addEvent('domready', map.init);