Dúvida cucumber

Preciso rodar o cucumber numa aplicação feita em Java -Swing aki na empresa que trabalho mas antes baixei uma outra aplicação da net em swing para testar o cucumber e tb montar o ambiente.

Estou obtendo o seguinte erro ao rodar o cucumber através do rake:

ti@ti07:~/Andre/projetos/demetriusnunes-swinger-c83dfc4$ rake Rakefile
(in /home/ti/Andre/projetos/demetriusnunes-swinger-c83dfc4)
ti@ti07:~/Andre/projetos/demetriusnunes-swinger-c83dfc4$ rake
(in /home/ti/Andre/projetos/demetriusnunes-swinger-c83dfc4)
/usr/bin/ruby1.8 -I "/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/lib:lib" "/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/cucumber" test/features --format progress
no such file to load -- java (LoadError)
/usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `gem_original_require'
/usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
/home/ti/Andre/projetos/demetriusnunes-swinger-c83dfc4/lib/swinger.rb:4
/usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `gem_original_require'
/usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:36:in `require'
/home/ti/Andre/projetos/demetriusnunes-swinger-c83dfc4/test/features/support/env.rb:1
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/rb_support/rb_language.rb:143:in `load'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/rb_support/rb_language.rb:143:in `load_code_file'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/runtime/support_code.rb:176:in `load_file'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/runtime/support_code.rb:78:in `load_files!'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/runtime/support_code.rb:77:in `each'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/runtime/support_code.rb:77:in `load_files!'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/runtime.rb:137:in `load_step_definitions'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/runtime.rb:39:in `run!'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/cli/main.rb:43:in `execute!'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/../lib/cucumber/cli/main.rb:20:in `execute'
/usr/lib/ruby/gems/1.8/gems/cucumber-0.10.2/bin/cucumber:14
rake aborted!
Command failed with status (1): [/usr/bin/ruby1.8 -I "/usr/lib/ruby/gems/1....]

Alguém sabe me dizer o pq esse erro ocorre ??? baixei a aplicação que comentei no seguinte site: https://github.com/demetriusnunes/swinger