While component software continues to grow in size and complexity, it becomes increasingly difficult to ensure qualities for component services, especially at run-time. This paper focuses on a framework on middleware for dynamic re-configuration of components of different qualities from the view of trust. Firstly, a trust management model is built, in which the management framework and measurement model are presented. Secondly, the reconfiguration algorithm is described based on the model. Thirdly, the trust management is implemented as a kind of public services and some tools on a J2EE-compliant middleware platform, i.e., PKUAS. Finally, the related work is discussed and compared with our research.