Unable to run working edge app with vendored rails.

$ ruby ~/Code/rails/railties/bin/rails edge_app
/Users/andriytyurnikov/Code/rails/actionpack/lib/action_dispatch.rb:28:in `require': no such file to load -- rack (LoadError)
    from /Users/andriytyurnikov/Code/rails/actionpack/lib/action_dispatch.rb:28
    from /Users/andriytyurnikov/Code/rails/railties/lib/rails.rb:6:in `require'
    from /Users/andriytyurnikov/Code/rails/railties/lib/rails.rb:6
    from /Users/andriytyurnikov/Code/rails/railties/bin/rails:23:in `require'
    from /Users/andriytyurnikov/Code/rails/railties/bin/rails:23

$ ruby -v
ruby 1.8.7 (2008-08-11 patchlevel 72) [universal-darwin10.0]

P.S. See ticket 2567 - same thing here?