Agents are an emerging technology that grants programmers a new way to exploit distributed resources. Roles are a powerful concept that can be used to model agent interactions, allowing agents to dynamically acquire operations to make specific tasks, and enabling separation of concerns and code reusability. Nevertheless roles should be developed taking into account permissions needed for the execution of their operations. The standard Java policy file mechanism does not suffice in this scenario, since a fine grain in managing permissions is required. This paper focuses on how to exploit the Java Authentication and Authorization Service (JAAS) at the role level in order to apply authorization and local policies to Java agents for limiting their operations.