$(document).ready(function(){
	
	img_tags = $(".rollover");
	
	$.each(img_tags, function(index, image){
		
		// preload "on" image
		
		
		// setup on function
		$(image).mouseover(function(){
			img = $(this);
			off_src = img.attr('src');
			on_src = off_src.replace('-off', '-on');
			img.attr('src', on_src);
		});
		
		// set up off function
		$(image).mouseout(function(){
			img = $(this);
			on_src = img.attr('src');
			off_src = on_src.replace('-on', '-off');
			img.attr('src', off_src);
		});
		
	});
	
});