The money guns were known as lilla. They could actually be fired. They also circulated on Sulawesi and Ceram. See OEANG* 156 and 224.
Apart from what is now Indonesia, miniature cannons were used as money in Brunei, Sabah and Sarawak. From
Odd & Curious and Traditional Money by Charles Opitz (page 148):
The cannons were used for trading purposes, barter of goods, payment of fines, and in wedding and engagement ceremonies. The cannons were fired during weddings, births of children and visits of important people.You can tell the canon on the coin is a miniature because the wheels are too small for the real thing. Also, the gun is put on a stand.
Peter
* R. Zaalberg, catalogus bij de tentoonstelling OEANG, ruil- en betaalmiddelen in Indiƫ (Arnhem 1999)