Fresh app won't run tests - uninitialized constant Rails::DeprecatedConstant::ActiveSupport

A fresh Rails 3 app created from the 3-0-stable branch won't run rake - it fails immediately with the error:

rake aborted!
uninitialized constant Rails::DeprecatedConstant::ActiveSupport
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2503:in `const_missing'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/deprecation.rb:26:in `method_missing'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/deprecation.rb:21:in `initialize'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/deprecation.rb:15:in `new'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/deprecation.rb:15:in `deprecate'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/deprecation.rb:38:in `<module:Rails>'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/deprecation.rb:4:in `<top (required)>'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails.rb:11:in `require'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails.rb:11:in `<top (required)>'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/all.rb:1:in `require'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bundler/gems/rails-4da32ba/railties/lib/rails/all.rb:1:in `<top (required)>'
/Users/Shared/rails3/as-test/config/application.rb:3:in `require'
/Users/Shared/rails3/as-test/config/application.rb:3:in `<top (required)>'
/Users/Shared/rails3/as-test/Rakefile:4:in `require'
/Users/Shared/rails3/as-test/Rakefile:4:in `<top (required)>'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2383:in `load'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2383:in `raw_load_rakefile'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2017:in `block in load_rakefile'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2016:in `load_rakefile'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2000:in `block in run'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/gems/rake-0.8.7/bin/rake:31:in `<top (required)>'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bin/rake:19:in `load'
/Users/nragaz/.rvm/gems/ruby-1.9.2-rc2@rails3/bin/rake:19:in `<main>'

Current rev is 4da32babdf04a151ec633cebf412fa6ca61e556d.

The Gemfile is just Rails from git and sqlite3-ruby.