HP MPI is not a part of a comprehensive parallel environment that manages parallel programs. This is not too bad on an Exemplar server, where there is a single system image, but can make is more difficult to run on a network of workstations.
HP provides several scripts for use with MPI. These include compiler scripts mpicc/CC and mpif77/f90, a program for listing currently running parallel jobs (mpijob), and a program for killing parallel jobs (mpiclean). Together, these provide a bit of an illusion of a parallel environment, but not quite as much as is needed. In particular, state is stored in the file system, rather than in daemons that can detect inconsistent state and react to it. There is no special handling of standard I/O for parallel jobs. HP MPI is also not integrated with a batch environment.