In Ankenbrandt v. Richards, 504 U.S. 689, 701-04, 112 S.Ct. 2206, 2213-15, 119 L.Ed.2d 468 (1992), the Supreme Court reaffirmed the validity of the "domestic relations exception" in diversity cases, but specifically limited application of that exception to divorce and alimony decrees and child custody orders.