I have been banging my head against the wall, and I finally found out what the problem is.
Basically, I was able to type latin characters like Ń, ˝, ¨, ˇ, etc...Except in OpenOffice.org. I have gone through the language configuration of OpenOffice.org's Tools menu with no luck. So, in OpenOffice.org, when I typed ß, nothing happened.
The problem came from the file ~/.login_conf, it was not set to function with UTF-8 the latest character set standard. I changed it to my language and using UTF-8 and now OpenOffice.org works like a charm:
# $FreeBSD: src/share/skel/dot.login_conf,v 1.3 2001/06/10 17:08:53 ache Exp $
# see login.conf(5)