The combination of personal computing devices and wireless ad-hoc networks allows the concept of mobile adhoc information system, consisting of a highly dynamic, decentralized and self-organizing network of autonomous and mobile devices that interact as peers[2, 3, 4]. Application developers have to deal with a new set of problems peculiar of these systems, due to user and terminal mobility, low bandwidth, transient loss of connectivity and lack of centralized infrastructure. It is evident that, for these classes of systems, applications cannot be designed according to the conventional architectural paradigms, such as for example the client-server one. On the contrary ”peer-to-peer” architectures are needed, where no single host is permanently seen as a server, but where each single host is able to play the role of server and client according the user’s needs. This means that an appropriate ”middleware” is needed, and must be able to provide appropriate architectural abstractions to upper applicative layers . This work goes towards this direction, trying to define a middleware layer, named Expeerience, that can answer to these issues: while doing this, we have decided to adopt as a basic software framework, an emerging P2P open technology such as JXTA . The second issue we address in this work is the integration of some code mobility support in the developed middleware to allow the distribution and execution of services on peers that originally do not own the service code. This has been introduced in our platform by adding a mobile code service, which enables to download and install new services dynamically only if necessary.