Default Ferret gem segfaults on freebsd

I installed the current version of ferret with “gem install ferret”, but
it don’t work.
When I do something at all with Ferret, I get this message:
[BUG] Segmentation fault
ruby 1.8.6 (2007-03-13) [i386-freebsd6]
Abort trap (core dumped)

Can someone please explain how to fix this, or make me found more
information about what happenes and why?