putEnv(env, Context.SECURITY_CREDENTIALS, credntials);
        if (providerUrl != null && providerUrl.startsWith("ldaps://")) {
            putEnv(env, Context.SECURITY_PROTOCOL, "ssl");
        }
        return env;
    }

    protected void putEnv(final Hashtable<String, String> env, final String key, final String value) {
        if (value == null) {