#> bin/mspec ci -t r -X /opt/work/jruby.git/test/spec_excludes spec/ruby/1.8/core/object/dup_spec.rb
ruby 1.8.6 (2007-06-07 patchlevel 36) [i486-linux]
./mspec/bin/options.rb:86:in `add_tags_dir': undefined method `[]=' for Config:Module (NoMethodError)
        from /usr/lib/ruby/1.8/optparse.rb:1291:in `call'
        from /usr/lib/ruby/1.8/optparse.rb:1291:in `parse_in_order'
        from /usr/lib/ruby/1.8/optparse.rb:1247:in `catch'
        from /usr/lib/ruby/1.8/optparse.rb:1247:in `parse_in_order'
        from /usr/lib/ruby/1.8/optparse.rb:1241:in `order!'
        from /usr/lib/ruby/1.8/optparse.rb:1332:in `permute!'
        from /usr/lib/ruby/1.8/optparse.rb:1353:in `parse!'
        from /usr/lib/ruby/1.8/optparse.rb:1343:in `parse'
        from ./mspec/bin/options.rb:261:in `parse'
        from mspec/bin/mspec-ci:48:in `options'
        from ./mspec/bin/script.rb:62:in `main'
        from mspec/bin/mspec-ci:71