Art. 76 OR; Art. 29 OG; engagement contract as family-law matter and limits of federal jurisdiction; an action for damages based exclusively on the alleged non-performance or unjustified dissolution of an engagement is to be assessed under cantonal law. Where the dispute is governed solely by cantonal law, the Federal Court has no jurisdiction to entertain the appeal for incompetence. The classification as a contractual damages claim ex contractu does not alter the applicable law when the underlying legal relationship belongs to family law. Consideration of the lower court’s solution is unnecessary once federal jurisdiction is excluded.