Rails 2.3.x use bleeding edges gems

In rails 3 you can us开发者_如何学JAVAe bleeding edge gems like: gem "devise", :git => "git://github.com/plataformatec/devise.git". How do you do that with config.gem in rails 2.3.x?

For that specific example I think you can do:

config.gem 'devise', :source => 'http://github.com/plataformatec/devise.git'

The best option is to use bundler on rails 2.3.x or switch to rails 3.

Heroku's docs are helpful: http://docs.heroku.com/bundler