validators.rb breaks after update from Rails 2.2.2 to 2.3.2

I just updated my rails application from 2.2.2 to 2.3.2 and the
following message is displayed while trying to start with ./script/
server:

[code]
=> Booting Mongrel
=> Rails 2.3.2 application starting on http://0.0.0.0:3000
/opt/local/lib/ruby/gems/1.8/gems/activesupport-2.3.2/lib/
active_support/core_ext/module/aliasing.rb:33:in `alias_method':
undefined method `valid?' for class `ActiveRecord::Base' (NameError)
  from /opt/local/lib/ruby/gems/1.8/gems/activesupport-2.3.2/lib/
active_support/core_ext/module/aliasing.rb:33:in `alias_method_chain'
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/callbacks.rb:224:in `send'
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/callbacks.rb:224:in `included'
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/callbacks.rb:223:in `each'
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/callbacks.rb:223:in `included'
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/base.rb:3143:in `include'
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/base.rb:3143
  from /opt/local/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/
active_record/base.rb:3137:in `class_eval'
   ... 11 levels...
  from /opt/local/lib/ruby/gems/1.8/gems/rails-2.3.2/lib/commands/
server.rb:84
  from /opt/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:
31:in `gem_original_require'
  from /opt/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:
31:in `require'
  from ./script/server:3
[/code]

I figured out that if I comment out "require 'validators.rb'" inside
my environment.rb than it'll work fine. Validators.rb (http://
pastie.org/457289) handles some special validations and sits in my lib
directory.

I am wondering what has changed from 2.2.2 to 2.3.2 that all the
sudden this rather simple extension wouldn't work anymore.

Does any have an idea?

JM

My guess would be some change to the load order - you'd be better off
loading your custom validations in an initializer, so that
ActiveRecord is loaded.

--Matt Jones