function BtPM2(flag, position)
{
if ((navigator.userAgent.indexOf("a/3",0) >= 0) || (navigator.userAgent.indexOf("a/4",0) >= 0))
  {
  var NewBtPM2 = eval(flag + ".src");
  document.images[position].src=NewBtPM2;
  }
}

if ((navigator.userAgent.indexOf("a/3",0) >= 0) || (navigator.userAgent.indexOf("a/4",0) >= 0))
{
BtPM21s =  new Image();
BtPM21s.src = "pics/prodmenu21.jpg";
BtPM21b =  new Image();
BtPM21b.src = "pics/prodmenu21b.jpg";
BtPM22s =  new Image();
BtPM22s.src = "pics/prodmenu22.jpg";
BtPM22b =  new Image();
BtPM22b.src = "pics/prodmenu22b.jpg";
BtPM23s =  new Image();
BtPM23s.src = "pics/prodmenu23.jpg";
BtPM23b =  new Image();
BtPM23b.src = "pics/prodmenu23b.jpg";
BtPM24s =  new Image();
BtPM24s.src = "pics/prodmenu24.jpg";
BtPM24b =  new Image();
BtPM24b.src = "pics/prodmenu24b.jpg";
BtPM25s =  new Image();
BtPM25s.src = "pics/prodmenu25.jpg";
BtPM25b =  new Image();
BtPM25b.src = "pics/prodmenu25b.jpg";
}