num = history.length;
num = (num % 3);
path = "addtop" + num + ".html";

addheader = document.createElement("iframe");
addheader.src = path;
addheader.width = 468;
addheader.height = 60;
addheader.frameBorder = 0;
addheader.scrolling="no";
addheader.allowTransparency = true;
addheader.hidefocus = true;
inspos0 = document.getElementById("header");
inspos1 = document.getElementById("header").firstChild;
inspos0.insertBefore(addheader, inspos1);