function smartRollover() {
	if(document.getElementsByTagName) {
		var images = document.getElementsByTagName("img");

		var images_pre = new Array();
		for(var i=0; i < images.length; i++) {
			if(images[i].getAttribute("src").match("_off.")) {
				images_pre[i] = new Image();
				images_pre[i].src = images[i].getAttribute("src").replace("_off.", "_on.")

				images[i].onmouseover = function() {
					this.setAttribute("src", this.getAttribute("src").replace("_off.", "_on."));
				}
				images[i].onmouseout = function() {
					this.setAttribute("src", this.getAttribute("src").replace("_on.", "_off."));
				}
			}
		}

		var globalNavi = document.getElementById("header").getElementsByTagName("ul")[0].getElementsByTagName("li");
		for(var i=0; i < globalNavi.length; i++) {
			if(globalNavi[i].getElementsByTagName("img")[0].getAttribute("src").match("_off.")) {
				birdBg(globalNavi[i], globalNavi[i].getElementsByTagName("img")[0]);
			}
		}
	}
}

function birdBg(obj,btn) {
	btn.onmouseover = function() {
		this.setAttribute("src", this.getAttribute("src").replace("_off.", "_on."));
		obj.className = "over";
	}
	btn.onmouseout = function() {
		this.setAttribute("src", this.getAttribute("src").replace("_on.", "_off."));
		obj.className = "";
	}
}

if(window.addEventListener) {
	window.addEventListener("load", smartRollover, false);
}
else if(window.attachEvent) {
	window.attachEvent("onload", smartRollover);
}