window.onload=function(){
$$('#knoppen .knop_purpel').each(function(el) { 
		el.addEvent('mouseenter',function(){
		//p = el.innerHTML.toUpperCase();
		//el.innerHTML = p;
		el.setStyle('background','url(images/knop_up.gif)');
		el.setStyle('background-repeat','no-repeat');
		//myEffect = el.effect('margin-left', {duration: 300,transition: Fx.Transitions.linear, wait: true}).start('10','30');
		})
		
		el.addEvent('mouseleave',function(){
		//p = el.innerHTML.toLowerCase();
		//el.innerHTML = p;
		el.setStyle('background','url(images/knop_down.gif)');
		el.setStyle('background-repeat','no-repeat');
		//myEffect = el.effect('margin-left', {duration: 900,transition: Fx.Transitions.Bounce.easeOut, wait: true}).start('30','0');
		})
	
	})
}