HTTP basic auth for Capybara

I'm writing some RSpec tests for my Rails 3 application and trying to switch from Webrat to Capybara. So far so good but the application uses HTTP basic auth to authorize my admin user, any idea how I can test that with Capybara?

Here is my current Webrat step:

it 'should authenticate for admin' do
  basic_auth('user', 'secret')
  visit '/admin'
  response.status.should eql 200
  response.status.should_not eql 401
end

How do I do this with Capybara? Thanks!