I have a test using Cucumber, capybara and selenium driver. This test should go to a form and submit it. The normal text would be
Scenario: Fill form
Give
You may probably roll your own step (And I submit the form with the link "Ok", for example), and emulate the submit functionality yourself.
Here it is the javascript emulation dropped in Rails 3 to support "unobtrusive" (emphasis on the quotes) Javascript. The line
Capybara::Driver::RackTest::Form.new(driver, js_form(self[:href], emulated_method)).submit(self)
is probably the clue to answer your problem. The full code is here