Error in xpath query when using dynamic fonts

[zenspider]

src: url('/webfonts/eot/style_190749.eot?#iefix') format('embedded-opentype'), url('/webfonts/woff/style_190749.woff') format('woff'), url('/webfonts/ttf/style_190749.ttf') format('truetype'), url('/webfonts/svg/style_190749.svg#Livory-Regular') format('svg');

causes:

/Users/ryan/.gem/sandboxes/deadweight/gems/nokogiri-1.5.5/lib/nokogiri/xml/node.rb:159:in `evaluate': Invalid expression: //svg(.) (Nokogiri::XML::XPath::SyntaxError)
    from /Users/ryan/.gem/sandboxes/deadweight/gems/nokogiri-1.5.5/lib/nokogiri/xml/node.rb:159:in `xpath'
    from /Users/ryan/.gem/sandboxes/deadweight/gems/nokogiri-1.5.5/lib/nokogiri/xml/node.rb:150:in `map'
    from /Users/ryan/.gem/sandboxes/deadweight/gems/nokogiri-1.5.5/lib/nokogiri/xml/node.rb:150:in `xpath'
    from /Users/ryan/.gem/sandboxes/deadweight/gems/nokogiri-1.5.5/lib/nokogiri/xml/node.rb:111:in `search'
    from /Users/ryan/.gem/sandboxes/deadweight/gems/deadweight-0.2.1/lib/deadweight.rb:42:in `analyze'
...