var banner = new Array();

banner.push("http://img10.imageshack.us/img10/1838/capturerzea.jpg");
banner.push("http://img140.imageshack.us/img140/2743/9thaxg7.jpg");

function changeLogo()
{
document.getElementById('i_logo').src= banner[Math.floor(Math.random()*banner.length)];

setInterval("document.getElementById('i_logo').src= banner[Math.floor(Math.random()*banner.length)];",3000);
}