diff --git a/MANIFEST b/MANIFEST
index dcbbe05c74..f4d86e3b56 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -164,6 +164,10 @@ lib/net/smtp.rb
 lib/net/telnet.rb
 lib/observer.rb
 lib/open3.rb
+lib/optparse.rb
+lib/optparse/shellwords.rb
+lib/optparse/time.rb
+lib/optparse/uri.rb
 lib/ostruct.rb
 lib/parsearg.rb
 lib/parsedate.rb