Lightweight and adaptable applications, essential for wearable and pervasive computing, are not systematically guaranteed when dealing with middleware based fault tolerance features. Some standards middlewares define heavy solutions not suitable for mobility. For example, Fault Tolerant CORBA (FT-CORBA) standard defines some services, like the replication manager, the fault notifier, etc. to handle the application replication. This approach is heavyweight, and the fault tolerant designed applications are not adaptable. This paper presents how Portable Request Interceptors (Pis), which we consider as a reflexive mechanism, could supply standard CORBA applications with fault tolerance in a lightweight, transparent, and adaptable way. Two distinct approaches are described: integration and service. In the first approach, fault tolerant mechanisms are Pis handled. Conversely, for the second one, Pis act as a "glue" between fault tolerant service and CORBA applications. Finally, conceptual limits, of these two approaches, and their influence on the fault tolerance deployment are discussed.
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