I found an easy way to install so51 under FreeBSD 3.3.
For this you should have a computer with linux on.
Go in linux, run de setup program als user, after this, go to your home
directory and make a tar archive from de directory Office51. Copy this
file on a place where you can reach it from FreeBSD, copy this file in
your BSD homedirectory, untar it and then simple run de office binary.
This works fine.