Error running the Awestruct Atomizer extension

gistfile1.sh

Generating: /home/bleathem/awestruct/site/_site/feed.atom
undefined method `fast_xs' for nil:NilClass
/var/lib/gems/1.9.1/gems/hpricot-0.8.6/lib/hpricot/traverse.rb:827:in `set_attribute'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/context_helper.rb:44:in `block in fully_qualify_urls'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/context_helper.rb:43:in `each'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/context_helper.rb:43:in `fully_qualify_urls'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/extensions/template.atom.haml:39:in `block (2 levels) in render'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/extensions/template.atom.haml:21:in `each'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/extensions/template.atom.haml:21:in `block in render'
/var/lib/gems/1.9.1/gems/haml-3.1.4/lib/haml/engine.rb:191:in `eval'
/var/lib/gems/1.9.1/gems/haml-3.1.4/lib/haml/engine.rb:191:in `render'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/handlers/haml_handler.rb:49:in `rendered_content'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/handlers/layout_handler.rb:48:in `rendered_content'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/page.rb:125:in `rendered_content'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/engine.rb:223:in `generate_page'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/engine.rb:211:in `block in generate_output'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/engine.rb:208:in `each'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/engine.rb:208:in `generate_output'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/engine.rb:59:in `run'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/cli/generate.rb:18:in `run'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/cli/invoker.rb:85:in `invoke_generate'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/lib/awestruct/cli/invoker.rb:39:in `invoke!'
/var/lib/gems/1.9.1/gems/awestruct-0.4.2.x6/bin/awestruct:8:in `<top (required)>'
/usr/local/bin/awestruct:19:in `load'
/usr/local/bin/awestruct:19:in `<main>'
[2012-05-16 11:41:52] INFO  WEBrick 1.3.1
[2012-05-16 11:41:52] INFO  ruby 1.9.2 (2011-07-09) [x86_64-linux]
[2012-05-16 11:41:52] INFO  WEBrick::HTTPServer#start: pid=4488 port=4242
Using inline Guardfile.
Ignoring paths: .awestruct, _tmp, _site
Guard is now watching at '/home/bleathem/awestruct/site'
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