if(navigator.appVersion.charAt(0) >=3){
  var btnimg = new Array();

  for( i = 0 ; i < 12 ; i++ ){
    btnimg[i] = new Image();
  }
//myboom
  btnimg[0].src=  "images/myboom1.png";
  btnimg[1].src=  "images/myboom2.png";
  btnimg[2].src=  "images/myboom3.png";
  btnimg[3].src=  "images/myboom4.png";
//yy
  btnimg[4].src=  "images/yy1.png";
  btnimg[5].src=  "images/yy2.png";
  btnimg[6].src=  "images/yy3.png";
  btnimg[7].src=  "images/yy4.png";
//lemon
  btnimg[8].src=  "images/lemon1.png";
  btnimg[9].src=  "images/lemon2.png";
  btnimg[10].src=  "images/lemon3.png";
  btnimg[11].src=  "images/lemon4.png";
}

function paintBtn(dim, cnt){
  if(navigator.appVersion.charAt(0) >= 3 ){
    document.images[dim].src=btnimg[cnt].src;
  }
}