Ruby 1.8.6 + Rails 1.2.3 + ErrorNotification == NameError !?

Hallo Everybody,

I updated recently to the latest versions of Ruby and Rails. Now it
seems to me that the plugin ErrorNotification doesn’t run anymore. I
even tried to create a new project, installed the plugin and added the
following line to my development.rb:

ExceptionNotifier.exception_recipients = "[email protected]"

When I try to start my server it hangs with an error. I tried it on
Mac and Windows, in development- and production-mode, with webrick and
mongrel and I’m always getting the following error:

/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/dependencies.rb:477:in const_missing': uninitialized
constant Rails::Initializer::ExceptionNotifiable (NameError)
        from /Users/dm/Documents/rails/pws_de/config/../config/
environments/development.rb:58:in load_environment'
        from /usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/
initializer.rb:204:in `load_environment'
        from /usr/local/lib/ruby/gems/1.8/gems/activesupport-1.4.2/lib/
active_support/core_ext/kernel/reporting.rb:11:in `silence_warnings'
        from /usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/
initializer.rb:201:in `load_environment'
        from /usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/
initializer.rb:85:in `process'
        from /usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/
initializer.rb:43:in `send'
        from /usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/
initializer.rb:43:in `run'
        from /Users/dm/Documents/rails/pws_de/config/environment.rb:13
         ... 11 levels...
        from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/
mongrel/command.rb:211:in `run'
        from /usr/local/lib/ruby/gems/1.8/gems/mongrel-1.0.1/bin/
mongrel_rails:243
        from /usr/local/bin/mongrel_rails:16:in `load'
        from /usr/local/bin/mongrel_rails:16

Has anybody an idea, what could be the problem?

Thanks in advance

Did anybody encounter a similar problem?

alright, I found the problem. i had rails 1.2.3.6906 installed.
uninstalled it and everything was working fine again.

ps: 1.2.3.71xx didn’t work either.