addEvent( window, 'DOMContentLoaded', function(){ init_roll(); } );

function init_roll() {
	
	if (!document.getElementById) return
	
	var arr_images = document.getElementsByTagName("img");
	var arr_preload = new Array();
	var temp;

	for (var i = 0; i < arr_images.length; i++) {		
		if (arr_images[i].className == 'rollover') {
		
			var src = arr_images[i].getAttribute('src');
			
			if (src.indexOf("-on") != -1) {
				src = src.replace("-on","");
			}
			
			var file_type = src.substring(src.lastIndexOf('.'), src.length);
			var image_src = src.replace(file_type, '-over'+file_type);

			arr_images[i].setAttribute('image_src', image_src);
			
			arr_preload[i] = new Image();
			arr_preload[i].src = image_src;
			
			arr_images[i].onmouseover = function() {
				temp = this.getAttribute('src');
				this.setAttribute('src', this.getAttribute('image_src'));
			}	
			
			arr_images[i].onmouseout = function() {
				if (!temp) temp = this.getAttribute('src').replace('-over'+file_type, file_type);
				this.setAttribute('src', temp);
			}
		}
	}
}

//window.onload = init_roll;