function createHover(){
	var menuImg = document.getElementById('mainMenu').getElementsByTagName("IMG");
	for (var i = 0; i < menuImg.length; i++) {
		menuImg[i].onmouseover = function() {this.src = String(this.src).replace(".gif","_active.gif");}
		menuImg[i].onmouseout = function() {this.src = String(this.src).replace("_active.gif",".gif");}
	}
}

if (window.attachEvent) {
	// IE-hez
	window.attachEvent("onload", createHover);
	
} else {
	// Jobbakhoz
	window.addEventListener("load", createHover, false);
	
}