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

		for(var i=0; i < images.length; i++) {
			if(images[i].getAttribute("src").match("off_"))
			{

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

		}
	}
}

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