Redmine

Whenever I create a copy of the configuration.yml.example file and try to set up a mail server, it makes Redmine hang forever when trying to visit the Settings page. The page just keeps loading indefinitely until I reset the service.

My mail settings as they are in configuration.yml:

production:
  email_delivery:
    delivery_method: :smtp
    smtp_settings:
      address: "smtp.ziggo.nl" 
      port: 25
      authentication: :plain
      domain: 'smtp.ziggo.nl'
      user_name: 'mymailaddress@home.nl'
      password: 'mypassword'

Note that Ziggo is my ISP and although the mail server is at smtp.ziggo.nl my mail address ends in @home.nl. I'm not sure if or how this is relevant, though since using sendmail results in the same problems, I'm guessing it's unrelated.

My production.log file has this as the last entry:

Started GET "/settings" for <IP> at 2012-08-16 16:16:24 +0000
Processing by SettingsController#index as HTML
  Rendered settings/_general.html.erb (47.7ms)
  Rendered settings/_display.html.erb (137.0ms)
  Rendered settings/_authentication.html.erb (36.6ms)
  Rendered settings/_projects.html.erb (41.8ms)
  Rendered settings/_issues.html.erb (96.9ms)
  Rendered settings/_notifications.html.erb (145.8ms)
  Rendered settings/_mail_handler.html.erb (15.7ms)

Note the lack of a "Completed 200 OK" or similar message at the end there.

Does this behavior sound familiar to anyone? What can I do to resolve this?

Relevant version info:

Environment:
  Redmine version                          2.0.2.stable
  Ruby version                             1.9.3 (x86_64-linux)
  Rails version                            3.2.5
  Environment                              production
  Database adapter                         Mysql2
Redmine plugins:
  no plugin installed