Redmine

I had followed the redmine installation instructions here: http://www.redmine.org/wiki/redmine/RedmineInstall
My environment: Redmine 0.8.4 on ubuntu 2.6.28-11-generic

I would like to start two distinct redmine instances simultaneously if possible. Possibly something like this:

ruby script/server webrick -e -d foo -port 3000
    ruby script/server webrick -e -d bar -port 4000

Inspired by the install instructions, I tried this:
rake db:migrate RAILS_ENV="foo"
First it complained that there is no foo.rb so I created it by copying it from config/environment/product.rb
Then I got the following error which complains that 'foo' database is not configured:

:/srv/www/redmine-0.8.4# rake db:migrate RAILS_ENV="foo" --trace

• Invoke db:migrate (first_time)
• Invoke environment (first_time)
• Execute environment
  rake aborted!
  foo database is not configured
  /srv/www/redmine-0.8.4/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb:218:
  `establish_connection'
  /srv/www/redmine-0.8.4/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb:209:
  `establish_connection'
  /srv/www/redmine-0.8.4/vendor/rails/railties/lib/initializer.rb:341:in `initialize_database'
  /srv/www/redmine-0.8.4/vendor/rails/railties/lib/initializer.rb:124:in `process'
  /srv/www/redmine-0.8.4/vendor/rails/railties/lib/initializer.rb:97:in `send'
  /srv/www/redmine-0.8.4/vendor/rails/railties/lib/initializer.rb:97:in `run'
  /srv/www/redmine-0.8.4/config/environment.rb:20
  ----------------------------------------------------

The instructions talk about creating "redmine" database, which I assume should support both 'foo' and 'bar'
How can I configure this 'foo' database?

Thanks in advance for your guidance ,
Kagan