The case of the day is Advanced Aerofoil Technologies AG v. Todaro (S.D.N.Y. 2011). The decision doesn’t go over the facts of the case; the complaint was for trade secret misappropriation. Some of the defendants were Americans, others were German or Swiss.
The plaintiff sought leave to serve the European defendants by courier (presumably, by FedEx or a similar service). But both Germany and Switzerland had objected to service by postal channels. The judge correctly denied the motion. Private couriers, according to US precedent as well as the view of the Hague Conference, come within the definition of postal channels.