cache_classes = true but they are not being cached

I am running my app in production mode on an apache2 web server but the
code is not be cached. That is, changes to code are being picked up
without having to restart the web server.

I would prefer this not to happen from a performance point of view.

I am running rails 1.1.6 and ruby 1.8.2

I know I am running in production mode as I can see the requests coming
up in the production.log file as I run the app.

My production.rb file is:

# Settings specified here will take precedence over those in

# The production environment is meant for finished, "live" apps.
# Code is not reloaded between requests
config.cache_classes = true

# Use a different logger for distributed setups
# config.logger =

# Full error reports are disabled and caching is turned on
config.action_controller.consider_all_requests_local = false
config.action_controller.perform_caching = true

# Enable serving of images, stylesheets, and javascripts from an asset
# config.action_controller.asset_host =

# send real emails
config.action_mailer.delivery_method = :smtp
#config.action_mailer.delivery_method = :test

# Disable delivery errors if you bad email addresses should just be
# config.action_mailer.raise_delivery_errors = false

Any ideas?