According to the testcase description the first part of the script tries to activate a session and specify a User which does not have access to the server and read the value of the (Security-)RejectedSessionCount. But the script does not check if the server has username authentication enabled, so for servers without the script sends a broken UserNameIdentityToken and expects the same results. This would be a completely different testcase, so this testcase should check if username authentication is available and skip the test if not.