if (document.image) {
   imgTop   = new Image(); imgTop.src   = "img/btn_top.gif";
   imgKite  = new Image(); imgKite.src  = "img/btn_Kites.gif";
   imgField = new Image(); imgField.src = "img/btn_Field.gif";
   imgDiary = new Image(); imgDiary.src = "img/btn_Diary.gif";
   imgMovie = new Image(); imgMovie.src = "img/btn_Movie.gif";
   imgBoard = new Image(); imgBoard.src = "img/btn_Board.gif";
   imgLink  = new Image(); imgLink.src  = "img/btn_link.gif";
}
function setImage(img, image) {
   if (img) {
      img.src = image;
   }
}