gistfile1.rb

module Devise
  module Strategies
    class MyAuthenticatable < Authenticatable

      def authenticate!
        begin
          if resp = authenticate_local
            
          else
            fail!('Invalid username or password')
          end
        rescue Error => e
          redirect! weak_password_path
        end

      end
    end
  end
end

Warden::Strategies.add(:pf_authenticatable, Devise::Strategies::PfAuthenticatable)

authenticate_local raises an exception, re-raising in rescue does not bubble up to Rails.

redirect! does not work