rspec users - Oct 2007 - Speccing a rake task

Greetings,

I''m writing a custom rake task, and I''d like to write an
assosciated spec for it.

Does anyone have an example spec for a rake task?

I''ve seen some examples on the web that use these before blocks:
  before(:each) do
    @rake = Rake::Application.new
    Rake.application = @rake
  end

And use 
  @rake["db:user_migration"].invoke

To invoke the task.  But this doesn''t seem to work for me.

Thanks for the help!

dan