function rollImage()
{
	var class_name = "roll";
	if(objPreload) delete objPreload;
	var objPreload = new Object();
	$("a img.roll").each(function(i) {
		var orgsrc = this.src;
		var oversrc = orgsrc.replace(/(\/).([^\/]+)$/, '$1o$2');
		objPreload[orgsrc] = new Image();
		objPreload[orgsrc].src = oversrc;
		$(this).hover(
			function(){ this.src = oversrc; },
			function(){ this.src = orgsrc; }
		);
	});
}
$(function(){ rollImage(); });