    <!--
    if (document.images) {
        aboutzgup       = new Image();
        aboutzgup.src   = "images/up/aboutzg.gif" ;
        aboutzgdown     = new Image() ;
        aboutzgdown.src = "images/down/aboutzg.gif" ;
        productsup       = new Image();
        productsup.src   = "images/up/products.gif" ;
        productsdown     = new Image() ;
        productsdown.src = "images/down/products.gif" ;
        servicesup       = new Image();
        servicesup.src   = "images/up/services.gif" ;
        servicesdown     = new Image() ;
        servicesdown.src = "images/down/services.gif" ;
                
        
        qcup       = new Image();
        qcup.src   = "images/up/qc.gif" ;
        qcdown     = new Image() ;
        qcdown.src = "images/down/qc.gif" ;
        piup       = new Image();
        piup.src   = "images/up/pi.gif" ;
        pidown     = new Image() ;
        pidown.src = "images/down/pi.gif" ;
        contactusup       = new Image();
        contactusup.src   = "images/up/contactus.gif" ;
        contactusdown     = new Image() ;
        contactusdown.src = "images/down/contactus.gif" ;
        
        eup       = new Image();
        eup.src   = "images/up/e.gif" ;
        edown     = new Image() ;
        edown.src = "images/down/e.gif" ;
        
        sup       = new Image();
        sup.src   = "images/up/s.gif" ;
        sdown     = new Image() ;
        sdown.src = "images/down/s.gif" ;
        
        cup       = new Image();
        cup.src   = "images/up/c.gif" ;
        cdown     = new Image() ;
        cdown.src = "images/down/c.gif" ;
        
    }
    function buttondown(btnDown)
    {
        if (document.images) {
          document[btnDown].src = eval( btnDown + "down.src" );          
        }
    }
    function buttonup (btnUp)
    {
        if (document.images) {
          document[btnUp].src = eval( btnUp + "up.src" );          
        }
    }
    // -->