Hi Ben,
Look forward to read the Wali Sanga book.
I have heard about it and even if I don't speak Dutch I can understand most of it by now with some deduction and imagination.
And I have participated, as the only outsider, in exorcistic rites in both East Kalimantan and Negros, Philippines.
Of course Filipino weapons are also believed to have metaphysical powers within them.
Actually I had some of my weapons "spirit-checked" around 9 years ago by a Filipino friend who has experience in those matters. He doesn't like that I collect old, and even worse - used, weapons for that reason.
Michael