Rails 1.2 was released earlier in the week with lots of cool new features but w/o ActiveResource or an ActiveResource gem. The good news is that you can add ActiveResource support by moving your application to edge rails and then check out ActiveResource as shown below.
>rails myapp
>cd myapp
>rake rails:freeze:edge
>cd vendor/rails
>svn co http://dev.rubyonrails.org/svn/rails/trunk/activeresource activeresourceNow you have a Rails app with ActiveResource support.
Note: I tried just checking ActiveResource into vendor/plugins but it conflicted with version 1.4.0 of ActiveSupport that ships with Rails 1.2. I had to move to edge rails to make it work.
As edge Rails can sometimes get messed up, I’ve found its easiest to lock on a stable revision. Latest stable release on 2/10 is 6145
rake rails:freeze:edge REVISION=6145
To see the latest stable revision number see: http://dev.rubyonrails.org/browser/branches