See Alaska Stat. We cannot determine from the record before us whether the facts relied on as a basis for upholding personal jurisdiction in McCaffery are present here. Further, because the parties have not addressed the issue, we do not decide whether, even in light of McCaffery , the Alaska court's exercise of personal jurisdiction over mother for purposes of ordering support was constitutionally permissible. A remand is thus required to determine mother's defense of lack of personal jurisdiction. On remand, the court in its discretion may permit the parties to supplement the record by providing evidence indicating whether an affidavit and return of service were ever filed with the Alaska court, as well as other evidence or argument necessary to determine whether the Alaska court could validly exercise personal jurisdiction over mother on the issue of support.
Mother raises two additional defenses to enforcement of the Alaska order.
Because the district court will need to address these defenses on remand if it determines that the Alaska court had personal jurisdiction over mother, we address her contentions here. A. Mother contends that even if the Alaska order is valid, the subsequent modification of the order by the parties' 1992 agreement constituted a defense to registration or enforcement of the order. The agreement between mother and father was never approved by any court. We conclude that the statute upon which mother relies, Colo. Sess. Laws 1991, ch.