JavaCards allow more than one application (called Applets) to coexist in them. This makes them very attractive, as the user can have, for example, a banking application, an e-wallet and his driving license in the same card. The JavaCard specification 2.1 provides applet developers with a way to share data and services between applets. This is called object sharing. In this paper, we put forward a methodology for secure object sharing on the JavaCard platform. Our proposal provides a methodogical solution to the problem identified by Montgomery and Krishna. That work is concerned with object sharing and proposes an approach to solve some of the problems that arise in the object sharing model proposed in the JavaCard 2.1 specification.