Service-Oriented Architecture supports the dynamic establishment of composite services issued from different organizations and delivers a large spectrum of innovative services. In such distributed environment, authentication and authorization processes require flexible access control to deal with heterogeneous services' directories and dynamic network of identity providers. Federated identity management and Single Sign-On (SSO) approaches enable identity management, authentication and access control. Unfortunately they are designed to operate in static and pre-defined collaboration scenarios and thus fail to cope with on the fly composition of services. In this paper we discuss the limitations of these approaches and then we present a solution that incorporates dynamic federated identity management and advanced authorization mechanism. We implement the solution through PEtALS Enterprise Service Bus (ESB) which is an open source highly distributed service-oriented middleware.