Vielleicht hilft dir das ja weiter:

AS400 system = new AS400();
ProgramCall pgm = new ProgramCall(system);
pgm.setThreadSafe(true); // Indicates the program is to be run on-thread.

public void setThreadSafe(boolean threadSafe)Specifies whether or not the program should be assumed thread-safe. The default is false.
Note: This method has no effect if the Java application is running remotely, that is, is not running "natively" on an IBM i system. When running remotely, the Toolbox submits all program calls through the Remote Command Host Server, regardless of the value of the threadSafe attribute.
Note: This method does not modify the actual program object on the system.
Note: If the program is run on-thread, it will run in a different job than if it were run off-thread.
Parameters:threadSafe - true if the program should be assumed to be thread-safe; false otherwise.