From the Malay World Edged Weapons site-
http://perso.wanadoo.fr/taman.sari/ -"The Malay Peninsula Lembing usually has a raised central ridge (ada-ada) and it is elongated. The shaft is decorated with a long ferrule with engraved silver or copper and a disk between the blade and the ferrule."
btw if we were to broaden the term from the earliest Spanish use "Moro" -interconnected groups would have included Muslim Malay kingdoms of Brunei, Makassar, Ternate, Tidore aside from Mindanao and Sulu, but classically we refer to the two later regions.