Rails 3 reset session using devise (actually not using devise)

application.rb

class ApplicationController < ActionController::Base
    ...
    before_filter :save_or_clear_session

    def save_or_clear_session
      if controller_name.eql?('sessions') and action_name.eql?('destroy')
        request.reset_session
        flash[:notice] = "Signed out successfully."
      end
    end
    ...
end