Can you use RSpec, Shoulda, RCov?

Question

I am attempting to get RCov to work with my RSpec and Shoulda test for a rails 3 app. It seems to work fine with my RSpec after using the Rake task below but all of the shoulda tests fail and I cant seem to find any documentation on getting these to work. They all run fine under autotest(rspec and shoulda).

namespace :spec do
  desc "Run specs with RCov"
  RSpec::Core::RakeTask.new('rcov' ) do |t|
    #t.spec_files = FileList['spec/**/*_spec.rb' ]
    t.rcov = true
    t.rcov_opts = ['--exclude' , '\/Library\/Ruby' ]
  end
end