The recent studies in the distributed simulation area are focused in the High Level Architecture, defined by the DoD/USA, which proposes a standard environment to develop and run distributed simulations. The HLA components are designed to ensure a high level of interoperability among simulations and, also, to allow maximum component reusability. This paper proposes a new mechanism to help optimist federates perform rollback procedures when needed. This mechanism uses computational reflection techniques to create a rollback manager meta-object that extends the low-level services provided by HLA.