I had this problem too. After searching all day I found a solution.
On BSD you need to have a converter installed.
/usr/ports/converters/ruby-iconv/
sudo make install clean
However, that did not solve the problem for me until I found this post:
"Just change RUBY_DEFAULT_VER?= in /usr/ports/Mk/bsd.ruby.mk from 1.8 on 1.9."
I removed the ruby-iconv and reinstalled it and problem is gone.
Good luck.
You might also try using TorqueBox (JRuby) on BSD…
On BSD you need to have a converter installed.
/usr/ports/converters/ruby-iconv/
Yeah when you install ruby if you look closely you'll see a post install message that says iconv is a separate port. It should read bigger.
"Just change RUBY_DEFAULT_VER?= in /usr/ports/Mk/bsd.ruby.mk from 1.8 on 1.9."
I removed the ruby-iconv and reinstalled it and problem is gone.
Yeah that's a trap everybody falls in. Once it's set, another version of ruby won't update the file.