CookieSource source = (CookieSource) sourceControl.getMock();
        MockControl requestControl = newControl(WebRequest.class);
        WebRequest request = (WebRequest) requestControl.getMock();
        ThreadLocale tl = newThreadLocale();
        // Training
        source.readCookieValue(TapestryConstants.LOCALE_COOKIE_NAME);
        sourceControl.setReturnValue(null);
        request.getLocale();
        requestControl.setReturnValue(Locale.JAPANESE);
        tl.setLocale(Locale.JAPANESE);
        replayControls();
        RequestLocaleManagerImpl manager = new RequestLocaleManagerImpl();
        manager.setCookieSource(source);