MPICH2 releases since the MPICH2-0.971 (released on 9 September 2004) have contained a PVFS v2 driver for ROMIO. Backporting the latest changes to older MPICH2 releases is fairly challenging. Users of PVFS v2 and ROMIO are encouraged to upgrade to the latest versions of MPICH2.
If for some reason you have to use an older version of MPICH2, the following patches might be useful. Upgrading to the latest version of MPICH2 is strongly encouraged. Please remember that these patches are historical only. To update the ROMIO in an older version of MPICH2 for your PVFS v2 installation, select one of the following patches.