Dynamic reconfiguration support in application servers is a solution to meet the demands for flexible and adaptive component-based applications. However, when an application is reconfigured, its fault-tolerant mechanism should be reconfigured either. This is one of the crucial problems we have to solve before a fault-tolerant application is dynamically reconfigured at runtime. This paper proposes a fault-tolerant sandbox to support the reconfigurable faulttolerant mechanisms on application servers. We present how the sandbox integrates multiple error detection and recovery mechanisms, and how to reconfigure these mechanisms at runtime, especially for coordinated recovery mechanisms. We implement a prototype and perform a set of controlled experiments to demonstrate the sandbox's capabilities.