var index = 0;
var imageName = new Array();

function preloadMenu(normal, over, current) {
     imageName[index] = new Array(3);
     imageName[index][0] = new Image();
     imageName[index][0].src = normal;
     imageName[index][1] = new Image();
     imageName[index][1].src = over;
     imageName[index][2] = new Image();
     imageName[index][2].src = current;
     
     index++;
     
     }

function mouseover(button, which) {
		button.src = "zimages/menu/over_" + which + ".jpg";
	}

function mouseout(button, which) {
		button.src = "zimages/menu/menu_" + which + ".jpg";
	}