This paper deals with the design and the development, of an intermediation middleware for supporting ubiquitous interaction based on a MAS (multi-agents system). These works are in the crossroads of HCI (human-computer interaction) and e-services area. We have studied researches about Web services, which appear insufficient for our needs. In this paper, we consider the intermediation between channels used by a user and e-services. Here we focus on the design and the implementation of this infrastructure and on the technologies that we have mobilised for this purpose