if (document.images) {
logoon = new Image(); // Active images
logoon.src = "graphics/logo2ar.jpg";

logooff = new Image(); // Inactive images
logooff.src = "graphics/logo2a.jpg";
}

function imgOn(imgName) {

if (document.images) {
document[imgName].src = eval(imgName + "on.src");
}
}

function imgOff(imgName) {
if (document.images) {
document[imgName].src = eval(imgName + "off.src");
}
}