function VS_swapImage(strImageName) {
    var x, ImageObj, pos, pos2
    ImageObj = document.getElementById(strImageName);
    pos = ImageObj.src.indexOf("_over.jpg");
    
    if (pos < 0) {
        pos2 = ImageObj.src.indexOf(".jpg");
        if (pos2 > 0) {
            ImageObj.src = ImageObj.src.substring(0, pos2);
            ImageObj.src = ImageObj.src + "_over.jpg";
        }
    }
}
function VS_swapOutImage(strImageName) {
    var x, ImageObj, pos, pos2
    ImageObj = document.getElementById(strImageName);
    pos = ImageObj.src.indexOf("_over.jpg");  
    if (pos > 0) {
        //pos2 = ImageObj.src.indexOf(".jpg");
        ImageObj.src = ImageObj.src.substring(0, pos);
        ImageObj.src = ImageObj.src + ".jpg";
    }
}