# File lib/polyamorous/activerecord_3_and_4.0_ruby_1.9/join_association.rb, line 5
    def self.included(base)
      base.class_eval do
        alias_method_chain :initialize, :polymorphism
        alias_method :equality_without_polymorphism, :==
        alias_method :==, :equality_with_polymorphism
        if base.method_defined?(:active_record)
          alias_method :base_klass, :active_record
        end

        if ActiveRecord::VERSION::STRING =~ /^3\.0\./
          alias_method_chain :association_join, :polymorphism
        else
          alias_method_chain :build_constraint, :polymorphism
        end
      end
    end