self.setInterval('loopMainImages()', 10*1000);

var num_images = 8; 
var current_image = 0; 

Images = new Array(num_images); 

for (i = 0; i < num_images; i++) { 
	Images[i] = new Image(); 
	Images[i].src = "/images/layout/main_teaser_"+i+".jpg"; 
} 

function loopMainImages() { 
	current_image = ((current_image+1)%num_images); 
	document.main_image.src = Images[current_image].src; 
}