if (document.images) {
    pic1= new Image(); 
    pic1.src="/ows/templates/hosting_01/images/button_red_rollover.gif"; 

    pic2= new Image(); 
    pic2.src="/ows/templates/hosting_01/images/button_blue_rollover.gif"; 

    pic3= new Image(); 
    pic3.src="/ows/templates/hosting_01/images/sidebar_button_red_rollover.jpg"; 

    pic4= new Image(); 
    pic4.src="/ows/templates/hosting_01/images/sidebar_button_blue_rollover.jpg"; 
}