Abstract. To enable an online virtual university, a learning environment covering the entire spectrum of the learning and management process is required. However, constructing such an environment remains a hard work. One of the problems is to integrate heterogeneous software modules from different providers. In addition, these modules must constantly evolve. In this paper, we propose CUBES, an e-learning enabling system that focuses on the integrity, evolvability and extensibility. In CUBES, a special data exchange module(DEM), along with a global authentication module and a core user information management module, forms a basic supporting platform for the integration of upper educational application modules(EAMs), e.g. a large scale real-time interactive virtual classroom and a dynamic learning quality monitor. A universal portal helps to configure the integrated EAMs, providing a seamless learning environment for users. With the help of the supporting system and the universal portal,...