if (document.images) { // Active Images
ff_on = new Image(); 
ff_on.src = "ff_on.gif"; 
ff_off = new Image(); 
ff_off.src = "ff_off.gif";

bio_on = new Image(); 
bio_on.src = "bio_on.gif"; 
bio_off = new Image(); 
bio_off.src = "bio_off.gif"; 

news_on = new Image(); 
news_on.src = "news_on.gif"; 
news_off = new Image(); 
news_off.src = "news_off.gif"; 

photos_on = new Image(); 
photos_on.src = "photos_on.gif"; 
photos_off = new Image(); 
photos_off.src = "photos_off.gif"; 

work_on = new Image(); 
work_on.src = "work_on.gif"; 
work_off = new Image(); 
work_off.src = "work_off.gif"; 

play_on = new Image(); 
play_on.src = "play_on.gif"; 
play_off = new Image(); 
play_off.src = "play_off.gif"; 
}

// Function to 'activate' images.
function imgOn(imgName) {
if (document.images) {
document[imgName].src = eval(imgName + "_on.src");
}
}

// Function to 'deactivate' images.
function imgOff(imgName) {
if (document.images) {
document[imgName].src = eval(imgName + "_off.src");
}
}