$(document).ready(function(){  
    $("#section_select a").hover(function(){
			var imgHref = $(this).children("img").attr("src")  //get the src of the thumbnail
    		$("#section select a").removeClass("selected");  //remove .selected class from all other links
    		$(this).addClass("selected");  //add .selected class to current link
			$("#image_holder .big").stop();
		$("#image_holder .big").stop().fadeTo(400, 0, function() {  //fade image out
    		$('#image_holder .big').attr('src',imgHref);  //give new image a src attribute    		
		}).fadeTo("slow", 1);  //fade the image in
	},function(){    //for onmouseout not used here
	});		
});