this(System.getProperty("jaaslounge.sso.jaas.config"));
    }


    public KerberosCredentials ( String loginContextName ) throws LoginException {
        LoginContext lc = new LoginContext(loginContextName);
        lc.login();
        this.subject = lc.getSubject();
    }


    public KerberosKey[] getKeys () {
        List<Key> serverKeys = new ArrayList<>();

        try {
            log.debug("Logging on");
            LoginContext lc;

	    Subject ps = super.getSubject();

            if ( this.configuration != null ) {
                lc = new LoginContext(this.serviceName, ps, this, this.configuration);
            }
            else if ( ps != null ) {
                lc = new LoginContext(this.serviceName, ps, this);
            } else {