Longbow says it's only a discipline weapon for Solar Wind. It's also a discipline weapon for Silver Crane.

Dwarven Longhammer is worth a mention for Dwarfs (Who are one of the top core options for most martial classes anyways). It's the Earthbreaker with reach (and more weight), plus it's from a "main" book and not Golarion speciffic, not worth an exotic weapon prof though. Problem is that its weapon group(s) is/are never actually given, though it should be a polearm and/or hammer.