Error Rails 3.0 pre Rack version incompatible

It appears that Rails 3.0pre installs a version of Rack (i.e. rack-1.0.2.pre.gem) that's incompatible with the installation of actionpack-3.0.pre.gem:

$ sudo rake install
Password:
(in /Users/conradwt/rails.dir/projects/rails)
mkdir -p pkg
  Successfully built RubyGem
  Name: rails
  Version: 3.0.pre
  File: rails-3.0.pre.gem
mv rails-3.0.pre.gem pkg/rails-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/activesupport)
mkdir -p pkg
  Successfully built RubyGem
  Name: activesupport
  Version: 3.0.pre
  File: activesupport-3.0.pre.gem
mv activesupport-3.0.pre.gem pkg/activesupport-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/activemodel)
mkdir -p pkg
  Successfully built RubyGem
  Name: activemodel
  Version: 3.0.pre
  File: activemodel-3.0.pre.gem
mv activemodel-3.0.pre.gem pkg/activemodel-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/actionpack)
mkdir -p pkg
WARNING:  deprecated autorequire specified
  Successfully built RubyGem
  Name: actionpack
  Version: 3.0.pre
  File: actionpack-3.0.pre.gem
mv actionpack-3.0.pre.gem pkg/actionpack-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/actionmailer)
mkdir -p pkg
WARNING:  deprecated autorequire specified
  Successfully built RubyGem
  Name: actionmailer
  Version: 3.0.pre
  File: actionmailer-3.0.pre.gem
mv actionmailer-3.0.pre.gem pkg/actionmailer-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/activeresource)
mkdir -p pkg
WARNING:  deprecated autorequire specified
  Successfully built RubyGem
  Name: activeresource
  Version: 3.0.pre
  File: activeresource-3.0.pre.gem
mv activeresource-3.0.pre.gem pkg/activeresource-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/activerecord)
mkdir -p pkg
WARNING:  deprecated autorequire specified
  Successfully built RubyGem
  Name: activerecord
  Version: 3.0.pre
  File: activerecord-3.0.pre.gem
mv activerecord-3.0.pre.gem pkg/activerecord-3.0.pre.gem
(in /Users/conradwt/rails.dir/projects/rails/railties)
mkdir -p pkg
WARNING:  bin/rails is missing #! line
  Successfully built RubyGem
  Name: railties
  Version: 3.0.pre
  File: railties-3.0.pre.gem
mv railties-3.0.pre.gem pkg/railties-3.0.pre.gem
  Successfully built RubyGem
  Name: arel
  Version: 0.2.pre
  File: arel-0.2.pre.gem
Successfully installed arel-0.2.pre
1 gem installed
(in /Users/conradwt/rails.dir/projects/rails/rack)
gem build rack.gemspec
WARNING:  bin/rackup is missing #! line
  Successfully built RubyGem
  Name: rack
  Version: 1.0.2.pre
  File: rack-1.0.2.pre.gem
Successfully installed rack-1.0.2.pre
1 gem installed
INSTALLING activesupport
Successfully installed activesupport-3.0.pre
1 gem installed
INSTALLING activemodel
Successfully installed activemodel-3.0.pre
1 gem installed
INSTALLING actionpack
ERROR:  Error installing actionpack/pkg/actionpack-3.0.pre.gem:
    actionpack requires rack (~> 1.1.0, runtime)
INSTALLING actionmailer
ERROR:  Error installing actionmailer/pkg/actionmailer-3.0.pre.gem:
    actionmailer requires actionpack (= 3.0.pre, runtime)
INSTALLING activeresource
Successfully installed activeresource-3.0.pre
1 gem installed
INSTALLING activerecord
Successfully installed activerecord-3.0.pre
1 gem installed
ERROR:  Error installing railties/pkg/railties-3.0.pre.gem:
    railties requires actionpack (= 3.0.pre, runtime)
ERROR:  Error installing pkg/rails-3.0.pre.gem:
    rails requires actionpack (= 3.0.pre, runtime)