undefined method `password' for FigNewton:Module (NoMethodError)

[snowe2010]

I get an undefined method error if I use a null or empty value in an environment file:

      undefined method `password' for FigNewton:Module (NoMethodError)
      ./lib/pages/login_page.rb:10:in `login_to_system'
      ./features/step_definitions/login_steps.rb:14:in `/^I logged into the portal$/'
      .\features\begin_test_setup.feature:4:in `Given I logged into the portal'

class LoginPage
  include PageObject

  page_url FigNewton.base_url + '//login.html'

  text_field(:username, :name => 'j_username')
  text_field(:password, :name => 'j_password')
  button(:login, :id => 'button')

  def login_to_system(username = FigNewton.username, password = FigNewton.password)
    self.username = username
    self.password = (password.nil? ? Settings.environment_password : password)

    login

    worklist = WorklistPage.new(@browser)
    worklist.wait_to_load
  end
end

base_url: http://awebsite.com:8080/

username: regular
password: ~

I'd like to be able to use null values if possible, using '' just doesn't work as well