/usr/share/man/man1/g_velacc.1.gz is in gromacs-data 5.0.2-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/gmx-velacc.1.gz
/usr/share/man/man1/gmx-velacc.1.gz