function startGalleryRotation(selector,delay){ 
	var i = 0; 
	var layers = $$(selector); 
	delay = (delay == undefined)? 6000:delay; 
	setInterval(function(){
		layers[i].set('tween', {duration: '3000'}); 
		layers[i].fade(0); 
		i = (i == layers.length-1)? 0 : i+1; 
		layers[i].fade(1); 
	},delay); 
	}

window.addEvent('domready', function() {
	startGalleryRotation('#slideshow_el li',6000); 
})