Rails 3 -NoMethodError (undefined method `original_filename

Hello! I'm using Rails 3, Uploadify, to send images to S3.

Right now all the images being uploaded to S3 have the MIME:
application/octet-stream

I'd like to fix that but I'm getting the following error:

    NoMethodError (undefined method `original_filename' for
#<ActiveSupport::HashWithIndifferentAccess:0x107c81998>):
      app/models/photo.rb:29:in `upload_file='
      app/controllers/photos_controller.rb:15:in `upload'
      app/middleware/flash_session_cookie_middleware.rb:14:in `call'

I think this is because all the tutorials out there aren't Rails 3
friendly. Anyone have any ideas? Here's the code:

    # Controller

    def create
    @photo = @photoalbum.photos.build(:upload_file => params[:photo])
      ...
    end

    # Model

    class Photo < ActiveRecord::Base
      require 'mime/types'
      ...
      def upload_file=(data)
        data.content_type =
MIME::Types.type_for(data.original_filename).to_s
        self.image = data
      end
    end