Hm, routing wars. Fun stuff. Expect much heat on this shortly... :( Essentially, the point-of-appeal would probably be the IEPG or NANOG mailing lists, and who would get believed would probably get worked out after some protracted flameage, consultations with lawyers, and arguments about how routing registry technologies will save the planet from routing wars, pollution, and too-strong coffee. My own personal advice wrt people who are thinking of using others' address space without permission is pretty simple: don't do it, you'll lose. Sean.