Mobile agents are an emerging approach to develop distributed and parallel applications. They also can be exploited to develop enterprise applications, since they can act as active network components, and can execute on heterogeneous platforms or architectures. In this paper we analyze the interaction issues of an agent based application for the automatic registration system of e-mail accounts, and we propose a role-based approach to deal with these interactions. Such an approach enables the development of flexible and reusable agent-based applications, which can also be exploited by enterprise systems to perform automatic or administrative tasks. Keyword: Agents, Role, Interactions