pages/Rails.md in oj-3.10.1 vs pages/Rails.md in oj-3.10.2

@@ -78,9 +78,47 @@
  * any other class where all attributes should be dumped
 
 The ActiveSupport decoder is the `JSON.parse()` method. Calling the
 `Oj::Rails.set_decoder()` method replaces that method with the Oj equivalent.
 
+### Usage in Rails 3
+
+To support Rails 3 you can create a new module mixin to prepend to controllers:
+
+```ruby
+require 'oj'
+
+module OjJsonEncoder
+  def render(options = nil, extra_options = {}, &block)
+    if options && options[:json]
+      obj = options.delete(:json)
+      options[:text] = Oj.dump(obj, :mode => :rails)
+      options[:content_type] = 'application/json'
+    end
+    super
+  end
+end
+```
+
+Usage:
+
+```ruby
+class MyController < ApplicationController
+  prepend OjJsonEncoder
+  def index
+    render :json => { :hello => 'world' }
+  end
+end
+```
+
+### Older Ruby Version Support (Pre 2.3.0)
+
+If you are using an older version of Ruby, you can pin `oj` to an earlier version in your Gemfile:
+
+```ruby
+gem 'oj', '3.7.12'
+```
+
 ### Notes:
 
 1. Optimized Floats set the significant digits to 16. This is different than
    Ruby which is used by the json gem and by Rails. Ruby varies the
    significant digits which can be either 16 or 17 depending on the value.