if (document.images) {
     button00a = new Image
     button00b = new Image
     button01a = new Image
     button01b = new Image
     button02a = new Image
     button02b = new Image
     button03a = new Image
     button03b = new Image
     button04a = new Image
     button04b = new Image


     button00a.src = 'images/menu/menu_001.png'
     button00b.src = 'images/menu/menu_01.png'
     button01a.src = 'images/menu/menu_002.png'
     button01b.src = 'images/menu/menu_02.png'
     button02a.src = 'images/menu/menu_003.png'
     button02b.src = 'images/menu/menu_03.png'
     button03a.src = 'images/menu/menu_004.png'
     button03b.src = 'images/menu/menu_04.png'
     button04a.src = 'images/menu/menu_005.png'
     button04b.src = 'images/menu/menu_05.png'

 }