Rakefile in stackprof-0.2.9 vs Rakefile in stackprof-0.2.10

@@ -14,10 +14,10 @@
 # Ruby Extension
 # ==========================================================
 
 require 'rake/extensiontask'
 Rake::ExtensionTask.new('stackprof', GEMSPEC) do |ext|
-  ext.ext_dir = 'ext'
+  ext.lib_dir = 'lib/stackprof'
 end
 task :build => :compile
 
 # ==========================================================
 # Testing