How to use acts_as_taggable_on with searchlogic!

post.rb

class Post < ActiveRecord::Base
  acts_as_taggable_on :categories

  # To deal with a single tag type... 
  scope_procedure :taggable_with_categories, lambda { |tags|
    tagged_with(tags, :on => :categories) 
  }

  # Or, deal with all your tag types...
  if respond_to?(:tag_types)
    tag_types.each do |tag_type|
      class_eval <<-EVAL
        scope_procedure :tagged_with_#{tag_type}, lambda { |tags| 
          tagged_with(tags, :on => :#{tag_type})
        }
      EVAL
    end
  end
end

some_controller.rb

# Use tagged_with_* just like you'd use other searchlogic scopes
Post.search(:tagged_with_categories => 'fun, awesome')