This paper briefly outlines the main characteristics of an ongoing research aimed at developing a support library for implementing systems based on autonomous agents. The library is built upon active objects, whose concurrent behavior is disciplined -for each controlled object- by a corresponding controller, according to the dictate of aspect-oriented programming. So far, we implemented a preliminary release of the library, with initial operational capabilities; in particular, agents are able to exhibit only a reactive behavior. To this end, a suitable architecture has been defined that embodies four subsystems, each one being able to deal with a different aspect: social ability, communication, behavior, and task execution. Agents' interaction and communication is performed according to the standard FIPA ACL. CLOS (Common Lisp Object System) has been adopted as the target language for implementing the library, according to the constraints imposed by an ongoing project, and for th...