Because of its inter-organisational, collaborative use of computational resources, grid computing presents a severe interoperability challenge to grid application developers. Different middleware technologies need to be bridged in order to fully utilise the power the grid provides. This paper describes a bridge between two such middlewares: The H2O Metacomputing Framework and Jini technology. The paper details how H2O resources may be registered, discovered and used as Jini1 services. Both technologies are introduced, design decisions discussed and a fully functional implementation presented.