var imageURL = new Array();
imageURL[1] = "image/menu/atuacao_on.jpg";
imageURL[2] = "image/menu/clientes_on.jpg";
imageURL[3] = "image/menu/contato_on.jpg";
imageURL[4] = "image/menu/home_on.jpg";
imageURL[5] = "image/menu/institucional_on.jpg";
imageURL[6] = "image/menu/trabalheconosco_on.jpg";

for(var i=0; i <= imageURL.length; i++) 
{
var image = new Image();
image.src = imageURL[i];
}

// JavaScript Document