Over the weekend, I released version 0.5 of the Cerberus gem.
The release included some better test support, as well as support for git branches and custom settings file inclusion for the Maven2 builder.
No, sooner had version 0.5 been released, then we began work in earnest on version 0.6
Mike Gunderloy has been working on adding features to Cerberus to support using a custom Ruby script as a project builder. The main reason, is to build the Rails project using their ci_setup.rb, CruiseControl build script.
The current code with Ruby builder support can be found in the ruby_builder branch of the main repository at the moment.
In addition, Mike wrote an excellent blog post on how he is building Rails using Cerberus and multiruby.