```ruby
# Add a callback - to be executed before each request in development,
# and at startup in production - to patch existing app classes.
# See http://stackoverflow.com/questions/7072758/plugin-not-reloading-in-development-mode
#
Rails.configuration.to_prepare do
    # Override mailer templates with theme ones. Note doing this in a before_filter,
    # as we do with the controller paths, doesn't seem to have any effect when
    # running in production
    ActionMailer::Base.view_paths.unshift File.join(File.dirname(__FILE__), "views")
end
```

Fix the "can't modify frozen array" error with Rails 3
user
```ruby
# Add a callback - to be executed before each request in development,
# and at startup in production - to patch existing app classes.
# See http://stackoverflow.com/questions/7072758/plugin-not-reloading-in-development-mode
#
Rails.configuration.to_prepare do
    # Override mailer templates with theme ones. Note doing this in a before_filter,
    # as we do with the controller paths, doesn't seem to have any effect when
    # running in production
    ActionMailer::Base.prepend_view_path File.join(File.dirname(__FILE__), "views")
end
```
assistant