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
     button05a = new Image
     button05b = new Image

     button00a.src = 'images/adsl_tel00a.gif'
     button00b.src = 'images/adsl_tel00b.gif'
     button01a.src = 'images/adsl_tel01a.gif'
     button01b.src = 'images/adsl_tel01b.gif'
     button02a.src = 'images/adsl_tel02a.gif'
     button02b.src = 'images/adsl_tel02b.gif'
     button03a.src = 'images/adsl_tel03a.gif'
     button03b.src = 'images/adsl_tel03b.gif'
     button04a.src = 'images/adsl_tel04a.gif'
     button04b.src = 'images/adsl_tel04b.gif'
     button05a.src = 'images/adsl_tel05a.gif'
     button05b.src = 'images/adsl_tel05b.gif'
 }