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.
Ah, but Sean, you missed the essential element of the previous post. Like so many other situations in the middle-east, you have two different factions, both of whom feel that they have legitimate title to the address space in question. Neither of them feels that it belongs to the other. Hence the conflict. The question boils down to who really does own the address space, and frankly, the fact that money changed hands causes me to lean more towads the person who paid. Owen