config.gem 'rspec'

I finally got rspec to install using config.gem (in Rails) with these lines:

  config.gem 'rspec',       :lib => 'spec'
  config.gem 'rspec-rails', :lib => false # Note this hack keeps it from failing on this gem.

...That allowed me to install/unpack them.  Which is all well and good.  But when I ran my specs, it failed, complaining about an "undefined method `evaluate_value_proc' for class `Spec::Matchers::Change'". Looking around, the claim was that this error was caused by "incompatible versions of rspec and rspec-rails". But that didn't jive with the versions I had installed.

So I commented out my two lines, above.  ...At least I had them in vendor/gems, (and my "script/generate rspec" bootstrap command ran fine, earlier).

With the gems commented out, everything worked.

[shrug]  Go figure.