Duplicidade no selectOneMenu... Socorro

<h:selectOneMenu id="nucleo" value="#{servicos.nucleo}">
            <f:selectItems value="#{menu.nucleo}"/>
         </h:selectOneMenu>

<managed-bean>
            <managed-bean-name>menu</managed-bean-name>
            <managed-bean-class>Configuracao.Menu</managed-bean-class>
            <managed-bean-scope>request</managed-bean-scope>
         </managed-bean>

public SelectItem[] getNucleo() throws SQLException {
        ln.buscarNucleo();
        nomeNucleo = ln.getNomeNucleo();
        codigoNucleo = ln.getCodigoNucleo();
        int size = ln.get_sizeN();
        SelectItem[] menuNucleo;
        menuNucleo = new SelectItem[size];

        for (int i = 0; i < size; i++) {
            menuNucleo[i] = new SelectItem(new String((String) codigoNucleo.elementAt(i)), (String) nomeNucleo.elementAt(i));
        }
        return menuNucleo;
    }

public void buscarNucleo() throws SQLException {
        Empresa em = new Empresa();
        buscar = em.buscarNucleo();
        try {
            stm = c.con.createStatement();
            rs = stm.executeQuery(buscar);
            if (rs.next()) {
                do {
                    nomeNucleo.addElement(rs.getString("DS_NUCLEO"));
                    codigoNucleo.addElement(rs.getString("CD_NUCLEO"));
                } while (rs.next());
            } else {
                informacao = "Nenhum nucleo localizada, entre em contato com o administrador";
            }
        } catch (SQLException e) {
            System.err.println("Erro buscarNucleo: " + e);
            informacao = "Informe o administrador\nERRO: " + e;
        }
        rs.close();
        stm.close();
    }