// this array consists of the id attributes of the divs we wish to alternate between
var divs_to_fade = new Array('box-1', 'box-2', 'box-3', 'box-4');

// the starting index in the above array.  It should be set to the value of the div which doesn't have the CSS Display property set to "none"
var i = 0;

// the number of milliseconds between swaps.  Default is five seconds.
var wait = 5000;

// the function that performs the fade
function swapFade() {
	Effect.Fade(divs_to_fade[i], { duration:1, from:1.0, to:0.0 });
	i++;
	if (i == 4) i = 0;
	Effect.Appear(divs_to_fade[i], { duration:1, from:0.0, to:1.0 });
}

// the onload event handler that starts the fading.
function startPage() {
	setInterval('swapFade()',wait);
}
			
Event.observe(window, 'load', startPage, false);