Newbie can't figure out how to install restful_authentication plugin

I get this message when I try to install restful_authentication plugin and I am stuck. I am running Windows Vista (don't ask...).

ruby script\plugin install -r 3072

git://github.com/technoweenie/restful-authentication.git c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_re quire': no such file to load -- ./script/../config/../vendor/rails/ railties/lib/ initializer (LoadError)         from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb: 27:in `re quire'         from ./script/../config/boot.rb:46:in `load_initializer'         from ./script/../config/boot.rb:39:in `run'         from ./script/../config/boot.rb:11:in `boot!'         from ./script/../config/boot.rb:109         from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb: 27:in `ge m_original_require'         from c:/ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb: 27:in `re quire'         from script/plugin:2

Ignore the -r 3072, that was from the svn location i tried. Output is the same.