try from the examples : java -jar lib/jruby.jar samples/fib.rb

hth,
Alia

----
Dear Shannon,

I too am interested in JRuby,  because I suspect that you could get a
little better results with Swing GUI's (  better control over "focus" and
certain defaults - maybe (?) ).      Plus,  it would be very nice to be
able to take advantage of some of the prebuilt libraries......  maybe even
database interfaces.      I haven't seen much documentation on this......I
don't even recall seeing a "tutorial" to explain how you would run a
program you wrote  [ ie: java -x  -y .......   hello.rb ] ..... of course
it has been a while.....    If you succeed with JRuby, please send me
whatever you are willing to share.

Thanks,
Greg