/usr/lib/x86_64-linux-gnu/libMapReduceMPI.so is in libmrmpi-dev 1.0~20131122-1build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libMapReduceMPI.so.1
/usr/lib/x86_64-linux-gnu/libMapReduceMPI.so.1