Event.observe(window, 'load', init);

function init(){
	var gallery = $$("img.gallery");
	for(var i = 0; i < gallery.length; i++){
		Event.observe(gallery[i], 'click', switchImage)
	}
}

function switchImage(e){
	var src = new String(Event.findElement(e, 'img').src);
	var el = $('parentImage');
	el.src = src.sub('icon', 'thumb', 1);
	var l = $('parentImageLink');
	l.href = src.sub('icon', 'big', 1);
}