$(function(){

	$("img.rollover").mouseover(function(){

		$(this).attr("src",$(this).attr("src").replace(/^(.+)(\.[0-9a-z]+)$/, "$1_down$2"));

	}).mouseout(function(){

		$(this).attr("src",$(this).attr("src").replace(/^(.+)_down(\.[0-9a-z]+)$/, "$1$2"));

	}).each(function(){

		$("<img>").attr("src",$(this).attr("src").replace(/^(.+)(\.[0-9a-z]+)$/, "$1_down$2"));

	});

});