diff --git a/example/Gemfile.lock b/example/Gemfile.lock
index 039adee0..44c07dae 100644
--- a/example/Gemfile.lock
+++ b/example/Gemfile.lock
@@ -89,7 +89,7 @@ GEM
     nanaimo (0.3.0)
     nap (1.1.0)
     netrc (0.11.0)
-    nkf (0.2.0)
+    nkf (0.3.0)
     prism (1.9.0)
     public_suffix (4.0.7)
     rexml (3.4.4)