// IMG SWAP AND NAV
function imgSwap(oImg)
{
   var strOver  = "_on";   // image to be used with mouse over
   var strOff = "_off";     // normal image
   var strImg = oImg.src;
   if (strImg.indexOf(strOver) != -1)
   {
      oImg.src = strImg.replace(strOver,strOff);
   }
   else
   {
      oImg.src = strImg.replace(strOff,strOver);
   }
}