diff --git a/liquid.gemspec b/liquid.gemspec
index 55103ae..bf85023 100644
--- a/liquid.gemspec
+++ b/liquid.gemspec
@@ -18,7 +18,7 @@ Gem::Specification.new do |s|
   s.required_rubygems_version = ">= 1.3.7"
 
   s.test_files  = Dir.glob("{test}/**/*")
-  s.files       = Dir.glob("{lib}/**/*") + %w(MIT-LICENSE README.md)
+  s.files       = Dir.glob("{lib,ext}/**/*") + %w(MIT-LICENSE README.md)
   s.extensions  = ['ext/liquid/extconf.rb']
 
   s.extra_rdoc_files  = ["History.md", "README.md"]