Need to get params back from some OAuth provider that doesn't let you explicitly pass them back? Though it's not (well?) documented, OmniAuth will store any existing params in request.env["omniauth.params"].

gistfile1.rb

# In your CallbacksController, pass omniauth.params:
    @user = User.find_for_PROVIDER_oauth(
      request.env["omniauth.auth"],
      request.env["omniauth.params"], 
      current_user
    )

# In your model, add a second parameter to the method definition:
  def self.find_for_PROVIDER_oauth(auth, params=nil, signed_in_resource=nil)

# And while you're poking around in your Devise model, you may want your oauth methods
# to set confirmed_at at creation.