function addEvent(object, evName, fnName, cap) {
   if (object.attachEvent)
       object.attachEvent("on" + evName, fnName);
   else if (object.addEventListener)
       object.addEventListener(evName, fnName, cap);
}

addEvent(window, "load", init, false);

function init() {
	var buttons = new Array();

	for (var i = 0; i < document.images.length; i++) {
		var button = document.images[i];
		if (button.className == "buttonImage") {
			buttons.push(button);
		}
	}

	for (var i = 0; i < buttons.length; i++) {
		//create a rollover 
		createRollOver(buttons[i]);
	}
}

function createRollOver(button) {
	button.out = new Image();
	button.over = new Image();
	
	button.out.src = button.src;
	button.over.src = button.src.replace(/Out/, "Over");
	
	button.onmouseout = function() {
		button.src = button.out.src;
	}
	
	button.onmouseover = function() {
		button.src = button.over.src;
	}
}