function displayRandomImage(imageName,array){
document.images[imageName].src=array[new Date().getTime()%array.length];
}
urls=["http://www.westfieldonweekends.org/files/nav_art01.jpg","http://www.westfieldonweekends.org/files/nav_art02.jpg","http://www.westfieldonweekends.org/files/nav_art03.jpg","http://www.westfieldonweekends.org/files/nav_art04.jpg","http://www.westfieldonweekends.org/files/nav_art05.jpg","http://www.westfieldonweekends.org/files/nav_art06.jpg","http://www.westfieldonweekends.org/files/nav_art07.jpg","http://www.westfieldonweekends.org/files/nav_art08.jpg","http://www.westfieldonweekends.org/files/nav_art09.jpg","http://www.westfieldonweekends.org/files/nav_art10.jpg","http://www.westfieldonweekends.org/files/nav_art11.jpg","http://www.westfieldonweekends.org/files/nav_art12.jpg","http://www.westfieldonweekends.org/files/nav_art13.jpg","http://www.westfieldonweekends.org/files/nav_art14.jpg","http://www.westfieldonweekends.org/files/nav_art15.jpg","http://www.westfieldonweekends.org/files/nav_art16.jpg","http://www.westfieldonweekends.org/files/nav_art17.jpg"]