if (document.images){ 
   
img1on = new Image();		
img1on.src = "images/nav_about.gif"; 
img2on = new Image();
img2on.src = "images/nav_sushi.gif";  
img3on = new Image();
img3on.src = "images/nav_entrees.gif";  
img4on = new Image();
img4on.src = "images/nav_party.gif"; 
img5on = new Image();
img5on.src = "images/nav_togo.gif";  
img6on = new Image();
img6on.src = "images/nav_customers.gif"; 
img7on = new Image();
img7on.src = "images/nav_join.gif"; 
img8on = new Image();
img8on.src = "images/nav_menu.gif"; 
img9on = new Image();
img9on.src = "images/nav_map.gif"; 


img1off = new Image();		  	
img1off.src = "images/nav_about_off.gif"; 
img2off = new Image();          
img2off.src = "images/nav_sushi_off.gif";
img3off = new Image();          
img3off.src = "images/nav_entrees_off.gif";
img4off = new Image();          
img4off.src = "images/nav_party_off.gif";
img5off = new Image();
img5off.src = "images/nav_togo_off.gif";  
img6off = new Image();
img6off.src = "images/nav_customers_off.gif"; 
img7off = new Image();
img7off.src = "images/nav_join.gif_off.gif"; 
img8off = new Image();
img8off.src = "images/nav_menu_off.gif"; 
img9off = new Image();
img9off.src = "images/nav_map_off.gif"; 

function imgOn(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "on.src");        }}
			
function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");        }}

}