HowTo have both development and production environment available from Apache with VirtualHost

To run both development and production environment using VirtualHost to choose between them here's the apache configuration :

LoadModule passenger_module /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.11/ext/apache2/mod_passenger.so

PassengerRoot /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.11
PassengerRuby /usr/local/bin/ruby

# Production redmine
<VirtualHost  *:80>
        ServerName redmine.mydomain.com
        RailsEnv production
        DocumentRoot /www/RoR/Redmine/redmine/public
        ErrorLog logs/redmine_error_log
        CustomLog logs/redmine_access_log combined

        <Directory  /www/RoR/Redmine/redmine/public>
                Allow from all
                Options -MultiViews
        </Directory>
</VirtualHost>

# Development (for testing purpose only - have its own db)
<VirtualHost  *:80>
        ServerName redminedev.mydomain.com
        RailsEnv development
        DocumentRoot /www/RoR/Redmine/redminedev/public
        ErrorLog logs/redminedev_error_log
        CustomLog logs/redminedev_access_log combined

        <Directory  /www/RoR/Redmine/redminedev/public>
                Allow from all
                Options -MultiViews
        </Directory>
</VirtualHost>