Rspec error while running jruby -S rake spec

Hello All,

I followed steps to install Rspec as in the link pasted below.

http://www.pmamediagroup.com/2009/04/tutorial-install-rspec-rails-factory-girl/

I have jRuby on Rails installed on my machine.Hence all commands need
to be run with jruby -S extension.
However when I run the jruby -S rake spec command,I get the following
error as shown below.