function imageSwitcher()
{
    aboutContent = document.getElementById('about-content');
    thumbs = document.getElementById('about-thumbnails');
    links = thumbs.getElementsByTagName('a');
    for (var i=0; i<links.length; i++) {
        links[i].onclick = toggleActive;
        // preload the images
        newImage = document.createElement('img');
        newImage.src = links[i].href;
    }
}


function toggleActive()
{
    // swap the image
    newImage = document.createElement('img');
    newImage.src = this.href;
    oldImage = aboutContent.getElementsByTagName('img')[0];
    aboutContent.replaceChild(newImage, oldImage);

    for (var i=0; i<links.length; i++) {
        if (links[i] == this) {
	    img = links[i].getElementsByTagName('img')[0];
            img.src = 'images/ico-on.gif';
        } else {
            img = links[i].getElementsByTagName('img')[0];
	    img.src = 'images/ico-off.gif';
        }
    }
    return false;
}
addLoadEvent(imageSwitcher);