function initRollOverImages() {
	var image_cache = new Object();
	$("dl#HeaderNav dd ul li a img, dl#GlobalNav dd ul li a img, div#MainContents p.Button a img, div#ExtraContents ul.Banner li a img").each(function(i) {
		var imgsrc = this.src;
		var dot = this.src.lastIndexOf('.');
		var imgsrc_on = this.src.replace(/_off/i, "_on");
		image_cache[this.src] = new Image();
		image_cache[this.src].src = imgsrc_on;
		$(this).hover(
			function() { this.src = imgsrc_on; },
			function() { this.src = imgsrc; });
	});
}
$(document).ready(initRollOverImages);