img1=new Image()
img1.src="http://www.discount-shopping-center.com/image/menu_home_hover.jpg"; 
img2=new Image()
img2.src="http://www.discount-shopping-center.com/image/menu_company_hover.jpg";
img3=new Image() 
img3.src="http://www.discount-shopping-center.com/image/menu_services_hover.jpg";
img4=new Image() 
img4.src="http://www.discount-shopping-center.com/image/menu_contactus_hover.jpg";
img5=new Image() 
img5.src="http://www.discount-shopping-center.com/image/menu_sitemap_hover.jpg";
img6=new Image() 
img6.src="http://www.discount-shopping-center.com/image/menu_resources_hover.jpg"; 

function menu_onmouseover(id)
{
    document.getElementById(id).setAttribute('src','http://www.discount-shopping-center.com/image/'+ id +'_hover.jpg');
}
function menu_onmouseout(id)
{
    document.getElementById(id).setAttribute('src','http://www.discount-shopping-center.com/image/'+ id +'.jpg');
}