This is part of what's causing the 1.8 failure: 1.8 doesn't support `respond_to_missing?`.  Instead you need to define `respond_to?`.  You could conditionally pick which one to define like [I did here](https://github.com/rspec/rspec-core/blob/master/spec/support/stderr_splitter.rb#L10-L13) or just define `respond_to?` since that also works on 1.9 (but doesn't allow a method object to be gotten for it -- so there's some implementation to fix as well, I think).