This paper describes a scheme of manipulating (partial) con- tinuations in imperative languages such as Java and C++ in a portable manner, where the portability means that this scheme does not depend on structure of the native stack frame nor implementation of virtual ma- chines and runtime systems. Exception handling plays a significant role in this scheme to reduce overheads. The scheme is based on program transformation, but in contrast to CPS transformation, our scheme pre- serves the call graph of the original program. This scheme has two im- portant applications: transparent migration in mobile computation and checkpointing in a highly reliable system. The former technology enables running computations to move to a remote computer, while the latter one enables running computations to be saved into storages.