Rejection of an objection to enforcement without security. There is no nullity in an arbitration award rendered in default of a party when that party was validly notified to appear at hearings and to submit its defense. Lack of standing of the respondent in the arbitration proceedings to allege a defect in the representation of the claimant (absence of a power of attorney granting authority to act in the arbitration proceedings) and thereby justify the nullity of the arbitration award: