if (document.images) {
     button1 = new Image
     button2 = new Image

     button1.src = 'common/images/home_up.gif'
     button2.src = 'common/images/home_dwn.gif'

	button3 = new Image
	button4 = new Image

	button3.src = 'common/images/mail_up.gif'
	button4.src = 'common/images/mail_dwn.gif'
 }