function hover() {
	if (document.getElementById) {
		var searchRegex = /hover/i;
		var images = document.getElementsByTagName("img");

		for (var i = 0; i < images.length; i++) {
			// If image has class "hover"
			if (-1 != images[i].className.search(searchRegex)) {
				var src = images[i].src;
				var lastDotPosition = src.lastIndexOf(".");
				var srcExt = src.substring(lastDotPosition, src.length);

				var hoverSrc = src.substring(0, lastDotPosition) + "_hover" + srcExt;

				images[i].hImg = new Image();
				images[i].hImg.src = hoverSrc;

				images[i].oImg = new Image();
				images[i].oImg.src = images[i].src;

				images[i].onmouseover = function() {
					this.src = this.hImg.src;
				};

				images[i].onmouseout = function() {
					this.src = this.oImg.src;
				};
			}
		}
	}
}

if (typeof window.addEventListener != "undefined") {
	window.addEventListener("load", hover, false);
} else if (typeof document.addEventListener != "undefined") {
	document.addEventListener("load", hover, false);
} else if (typeof window.attachEvent != "undefined") {
	window.attachEvent("onload", hover);
} else {
	if (typeof window.onload == "function") {
		window.currentOnload = window.onload;

		window.onload = function() {
			window.currentOnload();
			hover();
		};
	} else {
		window.onload = hover;
	}
}