Problem generating RSS feed with enclosures using FeedTools

I’m using the FeedTools library to generate an RSS feed with a media
enclosure. Unfortunately, I can’t seem to figure out how to add the
enclosure data.

Here is the code:

require ‘rubygems’
require_gem ‘feedtools’

feed = FeedTools::Feed.new
feed.title = ‘Odeo’
feed.link = ‘http://foo.com/profile/AlexCastro
feed.description = ‘Alex Channel’

feed.entries << FeedTools::FeedItem.new

feed.entries[0].title = ‘MacCast 12.22.2005’
feed.entries[0].link = ‘http://www.maccast.com
feed.entries[0].content = ‘A podcast about all things Macintosh. For
Mac geeks, by Mac geeks. Show 110. 1GB iPod Shuffles sold out until
January. Apples marketing group was considering a 1GB iPod Nano. Will
the first laptop…’
feed.entries[0].author = ‘MacCast’
feed.entries[0].issued = ‘Thu, 22 Dec 2005 10:04:35 GMT’
feed.entries[0].media_thumbnail_link =
http://images.odeo.com/4/2/4/mc_albumart.jpg

feed.entries[0].enclosures = FeedTools::FeedItem::Enclosure.new

feed.entries[0].enclosures.url =
http://foo.com/show/download/573556/1034567/paranode.com.topfunky.audio.2005.AviBryant.mp3
feed.entries[0].enclosures.type = “audio.mpeg”
feed.entries[0].enclosures.file_size = “24467810”

xml = feed.build_xml(‘rss’, 2.0)
puts xml

I receive the following error message:

NoMethodError: undefined method `size’ for
#FeedTools::FeedItem::Enclosure:0x13a69cc
method enclosures in feed_item.rb at line 1133