if (document.images)
   {
 
     texto = 0;
     faceon = new Image(13,13);
     faceon.src="img/lock_on.gif";
     
     faceoff = new Image(13,13);
     faceoff.src = "img/lock_off.gif";

   }

function lightuplock() {
   if (document.images) {
      imgOn=eval("faceon.src");
      document["lock"].src = imgOn;
   }
}

function turnofflock() {
   if (document.images) {
      imgOff=eval("faceoff.src");
      document["lock"].src = imgOff;
    }
}