The MPI::Fint type is included in a table in A.1.1 in MPI-2.1 (and 2.0), but it looks like its inclusion is a mistake. The issue is pretty simple; see the following for details: https://svn.mpi-forum.org/trac/mpi-forum-web/wiki/mpi22/MPI%3A%3AFint -- Jeff Squyres Cisco Systems