Cloning this repo is working, but the cloned app isn't

I cloned the repo http://github.com/dmonopoly/jdmedia with
git clone git://github.com/dmonopoly/jdmedia.git
and got the app and everything. It's an app in Rails 3, if that
matters.

Anyway, after "cd jdmedia" I find that the app doesn't work, when I'm
sure the app should.
for example, typing rails -v or any rake command brings up this error:

undefined method `[]' for nil:NilClass

For the rails -v command, I get this:

C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/bundler/
lockfile_parser.rb:48:in `parse_source': undefined
method `[]' for nil:NilClass (NoMethodError)
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/lockfile_parser.rb:20:in `send'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/lockfile_parser.rb:20:in `initialize'

        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/lockfile_parser.rb:14:in `each'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/lockfile_parser.rb:14:in `initialize'

        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/definition.rb:43:in `new'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/definition.rb:43:in `initialize'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/dsl.rb:122:in `new'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/dsl.rb:122:in `to_definition'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler/definition.rb:20:in `build'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler.rb:128:in `definition'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler.rb:116:in `load'
        from C:/Ruby187/lib/ruby/gems/1.8/gems/bundler-1.0.0/lib/
bundler.rb:100:in `setup'
        from C:/Documents and Settings/David Zhang/workspace/mediasite/
config/boot.rb:8
        from script/rails:5:in `require'
        from script/rails:5

The rails -v command works in other apps I have on my machine...so
what is going on?
Thanks in advance.