Providing NTLM credentials for a http proxy via system properties never get read

-Dhttp.proxyHost=TheUrlToTheNtmlProxy
-Dhttp.proxyPort=8080
-Dhttp.proxyUser=TheUsersName
-Dhttp.proxyPassword=TheUsersPassword
-Dhttp.auth.ntlm.domain=TheDomain

@Override
    public Credentials getCredentials(final AuthScope authscope) {
        Args.notNull(authscope, "Auth scope");
        final Credentials localcreds = internal.getCredentials(authscope);
        if (localcreds != null) {
            return localcreds;
        }
        if (authscope.getHost() != null) {
            PasswordAuthentication systemcreds = getSystemCreds(
                    authscope, Authenticator.RequestorType.SERVER);
            if (systemcreds == null) {
                systemcreds = getSystemCreds(
                        authscope, Authenticator.RequestorType.PROXY);
            }

//*** systemcreds is always null ***

            if (systemcreds != null) {
                final String domain = System.getProperty("http.auth.ntlm.domain");
                if (domain != null) {
                    return new NTCredentials(
                            systemcreds.getUserName(),
                            new String(systemcreds.getPassword()),
                            null, domain);
                } else {
                    if (AuthSchemes.NTLM.equalsIgnoreCase(authscope.getScheme())) {
                        // Domian may be specified in a fully qualified user name
                        return new NTCredentials(
                                systemcreds.getUserName(),
                                new String(systemcreds.getPassword()),
                                null, null);
                    } else {
                        return new UsernamePasswordCredentials(
                                systemcreds.getUserName(),
                                new String(systemcreds.getPassword()));
                    }
                }
            }
        }
        return null;
    }