var RollImgOldSrc = '';
function RollImg(oImg, NewSrc)
{
    RollImgOldSrc = oImg.src;
    
    oImg.src = NewSrc;
    
    //oImg.onmouseout = "function(event){this.src = '" + RollImgOldSrc + "';};";
    oImg.onmouseout = function(event){this.src = RollImgOldSrc; this.onmouseout = null;};
}