Which is correct? Brunei or Berunai?

Someone asked on the comment box which I copied Nazri: kn betanya, kenapa nama ejaan Brunei B.R.U.N.E.I? Sedangkan sebutannya BRUNAI? nda pernah ku tejumpa mana-mana ejaan yang berakhir dengan E.I disebut "ai".Nazri brought up an interesting point. When did 'Brunei' became Brunei?I will ignore the old Chinese reports which used various names such as Poli and Poni and concentrates on the word