if (document.images) 
{
image1 = new Image
image2 = new Image
image3 = new Image
image4 = new Image
image1.src = 'images/flagned_d.gif' 
image2.src = 'images/flagned.gif' 
image3.src = 'images/flageng_d.gif' 
image4.src = 'images/flageng.gif' 
}