if (document.images) {            // Active Images
img1on = new Image();      
img1on.src = "buttons/but_home_over.gif"; 
img2on = new Image();      
img2on.src = "buttons/but_about_over.gif"; 
img3on = new Image();      
img3on.src = "buttons/but_projects_over.gif"; 
img4on = new Image();      
img4on.src = "buttons/but_world_over.gif"; 
img5on = new Image();      
img5on.src = "buttons/but_shop_over.gif"; 
img6on = new Image();      
img6on.src = "buttons/but_sitemap_over.gif"; 
img8on = new Image();      
img8on.src = "buttons/but_visitus_over.gif"; 
img7on = new Image();      
img7on.src = "buttons/but_contact_over.gif"; 
img9on = new Image();      
img9on.src = "buttons/but_how_over.gif"; 

img1off = new Image(); 
img1off.src = "buttons/but_home.gif"; 
img2off = new Image(); 
img2off.src = "buttons/but_about_over.gif"; 
img3off = new Image(); 
img3off.src = "buttons/but_projects.gif"; 
img4off = new Image(); 
img4off.src = "buttons/but_world.gif"; 
img5off = new Image(); 
img5off.src = "buttons/but_shop.gif"; 
img6off = new Image(); 
img6off.src = "buttons/but_sitemap.gif"; 
img8off = new Image(); 
img8off.src = "buttons/but_visitus.gif"; 
img7off = new Image(); 
img7off.src = "buttons/but_contact.gif"; 
img9off = new Image(); 
img9off.src = "buttons/but_how.gif"; 
}

// Function to 'activate' images.
function imgOn(imgName) {
   if (document.images) {
       document[imgName].src = eval(imgName + "on.src");
     }
}

// Function to 'deactivate' images.
function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");
        }
}