FYI, Cheri has now been updated to 0.0.5, and the Cheri::JRuby::Explorer (CJX) demo app now runs cleanly. If you downloaded the initial release(s) over the weekend, please get the update! Much, much better now. Still working on the doc, out soon.
Cheers, -Bill http://rubyforge.org/projects/cheri http://cheri.rubyforge.org/