function newImage(arg) {
		if (document.images) {
			rslt = new Image();
			rslt.src = arg;
			return rslt;
		}
	}
	
	function changeImages() {
		if (document.images && (preloadFlag == true)) {
			for (var i=0; i<changeImages.arguments.length; i+=2) {
				document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
			}
		}
	}
	
	var preloadFlag = false;
	function preloadImages() {
		if (document.images) {
			home_over = newImage("/images/header/home_over.gif");
			home_down = newImage("/images/header/home_down.gif");
			resources_over = newImage("/images/header/resources_over.gif");
			resources_down = newImage("/images/header/resources_down.gif");
			community_over = newImage("/images/header/community_over.gif");
			community_down = newImage("/images/header/community_down.gif");
			join_over = newImage("/images/header/join_over.gif");
			join_down = newImage("/images/header/join_down.gif");
			about_over = newImage("/images/header/about_over.gif");
			about_down = newImage("/images/header/about_down.gif");
			preloadFlag = true;
		}
	}