function rOver(oImg) {
  var cSrc = oImg.src;
  var rRO  = /_ro\./;
  if (!rRO.test(cSrc)) {oImg.src = cSrc.replace(/.jpg/,"_ro.jpg");}
}
function rOut(oImg) {
  var cSrc = oImg.src;
  var rRO  = /_ro\./;
  if (rRO.test(cSrc)) {oImg.src = cSrc.replace(/_ro.jpg/,".jpg");}
}