The paper reports on a new middleware architecture suggested for seamless handover. The middleware is part of an architectural solution suggested by Blekinge Institute of Technology (BTH) for seamless handover, which is implemented at the application layer. This architecture is sub ject for the PERIMETER STREP and MOBICOME pro jects, granted by the EU FP7 and EUREKA, respectively. Compared to the existent handover solutions, implemented at the link layer and network layer, this solution offers the advantage of less dependence on physical parameters and more flexibility in the design of architectural solutions. Furthermore, it allows for dynamic combinations of services and underlying transport substrates (overlays and networks). The suggested middleware, called ROMA, represents a software system with two sets of APIs, one for application writers and another one for interfacing various overlay and un- derlay systems. ROMA thus provides a transport-agnostic platform for future Internet applications. The paper provides a short description of the ROMA middleware, with par- ticular focus on API design and address translation.