function rollover() {
	$(".rollover").each(
		function () {
			$(this).mouseover(
                function () {
					$(this).attr("src", $(this).attr("src").replace(/\.([^.]*)$/, "_o.$1"));
				}
			);
			
			$(this).mouseout(
                function () {
                    $(this).attr("src", $(this).attr("src").replace(/_o\.([^.]*)$/, ".$1"));					
				}
			);
		}
	);
}
$(rollover);