Ruby script/plugin install

I am trying to migrate a rails app from the rails 2.x world (which was
the
last time I worked with rails) and I’m trying to run the command:

ruby script/plugin install
git://github.com/activescaffold/active_scaffold.git --force

which returns:

/home/user/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:53:in
require': cannot load such file -- script/../config/boot (LoadError) from /home/user/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/site_ruby/2.0.0/rubygems/core_ext/kernel_require.rb:53:inrequire’
from script/plugin:2:in `’

evidently this command is deprecated in ruby 2.0.0p247 (with rails
4.0.0).
Can anyone tell me how this command might be specified nowadays (under
ruby
2.0.0 ?). Thanks, RVic