They had a translator, Magellan's servant, a native from the Malaccas Straits (now the areas which bound Johore Bahru, Singapore & Batam) who was captured in the war vs. the Moors in the Mediterranean Sea & Middle East. Bahasa was the lengua franca of the area in the scope of the Sultanate of Sulu who had diplomatice relations with Ching, the Moghuls & Ottoman Empires.
When Magellan was killed, he returned to Melaka. He probably circumnavigated the world before Magellan et al did because he started & ended up home before everyone else.
Want to know more about Enrique de Melaka? Check:
http://www.sabrizain.demon.co.uk/malaya/port3.htmDon't you love the internet?