Groupware applications, acquire more importance; within a mobile computing environment, users need to interact, to conform communities and to pursue common objectives without concerning about their individual context. This paper presents the Ayllu architecture, which is intended to develop groupware applications with a cooperative approach, called 5C paradigm. The fundamental idea is that cooperation between people must be carried out by explicit mechanisms supporting collaboration, coordination and conflict resolution, which are supported by intentional communication acts. A middleware based on this approach has been constructed. It uses software agents as mediators between users working cooperatively. Agents act together to support cooperative services by means of a mechanism, called volatile group. Agent groups are created dynamically, well-defined agent interaction protocols allow to provide the communication patterns that support people cooperation. The Ayllu architecture also includes means to deal with the inherent limitations of mobile devices.