$(document).ready(function(){
	$("#nav_top a").append("<em></em>");
	
	$("#nav_top a").hover(
		function() {
			var hoverText = $(this).attr("title");
			var intTop = 0;
			if ( ie ) intTop += 18;
			switch(this.id) {
				case "pi":
				case "cpp":
					intTop -= 62;
					break;
				case "pmg":
				case "gu":
				case "rems":
					intTop -= 79;
					break;
			}
			$(this).find("em").animate({opacity: "show", top: intTop}, "normal");
			$(this).find("em").html(hoverText);
		},
		function() {
			var intTop = 0;
			if ( ie ) intTop += 18;
			switch(this.id) {
				case "pi":
				case "cpp":
					intTop -= 42;
					break;
				case "pmg":
				case "gu":
				case "rems":
					intTop -= 59;
					break;
			}
			$(this).find("em").animate({opacity: "hide", top: intTop}, "slow");
		}
	);

});

function nav_top_swapImage(obj) {
	obj.src=obj.src.indexOf("_on.gif")>-1?obj.src.replace("_on.gif",".gif"):obj.src.replace(".gif","_on.gif");
}