Update from RoR 1.1.6 - 1.2.3 Rake fails

I am getting a message when I update my system from rails 1.1.6 to
1.2.3 running rake.

[]# rake test --trace
(in /var/www/matrix.1.7.15)
** Invoke test (first_time)
** Execute test
** Invoke test:units (first_time)
** Invoke db:test:prepare (first_time)
** Invoke environment (first_time)
** Execute environment
rake aborted!
Expected /var/www/matrix.1.7.15/config/../vendor/plugins/
exception_notification/lib/exception_notifier.rb to define
ExceptionNotifier
/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:249:in `load_missing_constant'
/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:452:in `const_missing'
/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:464:in `const_missing'
/var/www/matrix.1.7.15/config/../config/environment.rb:75
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in
`require'
/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:495:in `require'
/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:342:in `new_constants_in'
/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:495:in `require'
/usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/tasks/misc.rake:3

If I remove the ExceptionNotifier lines from my environment.rb file
this problem goes away, but I get similar problems trying to access my
ActiveRecord objects within script/console

PlanProcedure.find(:all)

LoadError: Expected script/../config/../config/../app/models/
plan_procedure.rb t o define PlanProcedure
        from /usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_su pport/dependencies.rb:249:in `load_missing_constant'
        from /usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_su pport/dependencies.rb:452:in `const_missing'
        from /usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_su pport/dependencies.rb:464:in `const_missing'
        from (irb):1

Can someonehelp me out with updating a system from 1.1.6 to 1.2.3. Am
I missing something here.
My gems are actionmailer (1.3.3, 1.2.5)
    Service layer for easy email delivery and testing.

actionpack (1.13.3, 1.12.5)
    Web-flow and rendering framework putting the VC in MVC.

actionwebservice (1.2.3, 1.1.6)
    Web service support for Action Pack.

activerecord (1.15.3, 1.14.4)
    Implements the ActiveRecord pattern for ORM.

activesupport (1.4.2, 1.3.1)
    Support and utility classes used by the Rails framework.