We consider the challenge of dynamically adapting services to context changes that occur in ubiquitous computing environments (e.g., changes in a user's activity) and propose the Context-Aware Service Enabling (CASE) platform for that purpose. The CASE platform combines context-aware service discovery with service composition, acting as an enabler for the development of adaptive context-aware applications. In this paper, we illustrate the need for context-aware service discovery and composition in pervasive 4G environments and present the architecture of the CASE platform. The CASE platform enables applications to easily adapt to changes in service availability, which may result from changes in client and/or service context. We also provide an overview of the platform's technical realization.