function newImage(arg) {
if (document.images) {
rslt = new Image();
rslt.src = arg;
return rslt;
}
}

function changeImages() {
if (document.images && (preloadFlag == true)) {
for (var i=0; i<changeImages.arguments.length; i+=2) {
document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
}
}
}

var preloadFlag = false;
function preloadImages() {
if (document.images) {
nav_01_gala_o = newImage("http://www.iatp.org/20years/img/nav_01_gala_o.gif");
nav_02_honorees_o = newImage("http://www.iatp.org/20years/img/nav_02_honorees_o.gif");
nav_03_hosts_o = newImage("http://www.iatp.org/20years/img/nav_03_hosts_o.gif");
nav_04_tickets_o = newImage("http://www.iatp.org/20years/img/nav_04_tickets_o.gif");
nav_05_history_o = newImage("http://www.iatp.org/20years/img/nav_05_history_o.gif");
nav_06_events_o = newImage("http://www.iatp.org/20years/img/nav_06_events_o.gif");
nav_07_home_o = newImage("http://www.iatp.org/20years/img/nav_07_home_o.gif");
preloadFlag = true;
}
}