random_image = new Object();
random_image.interval = 5000;

random_image.imagesList = new Array();

random_image.attachImages = function(images) {
	for(var i=0; i<images.length; i++) {
		random_image.imagesList[i] = new Image();
		random_image.imagesList[i].src = images[i];
	}
}

random_image.getRandomImage = function() {
	var random = Math.floor(Math.random() * random_image.imagesList.length);
	setInterval('random_image.reloadImage();', random_image.interval);
	return '<img src="' + random_image.imagesList[random].src + '" id="random_image_src" />';
}

random_image.reloadImage = function() {
	var random = Math.floor(Math.random() * random_image.imagesList.length);
	var obj = (document.getElementById) ? document.getElementById('random_image_src') : document.all['random_image_src'];
	if(obj == null) return;
	obj.src = random_image.imagesList[random].src;
}