Abstract: The present invention provides a technique for providing high speed reactivation of an agent received by a receiving computer environment from a sending computer environment. Each agent maintains not only the names of programs necessary for its execution but also version information for the necessary programs. Preferably, each agent execution environment includes a cache mechanism which stores program code for programs that are used in agents as well as the names and the version identifiers of the programs. During the transfer of an agent, the name and version information for programs required by the agent are placed at the beginning of a bit sequence, with state data and program code following. The bit sequence is then transmitted. By employing the received name and version information, the execution environment at the destination utilizes, to the extent possible, program code that is held in the cache mechanism, or, if program code is not cached, utilizes the program code that is received.