diff --git a/Gemfile.lock b/Gemfile.lock
index 716464f..8631f12 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -178,8 +178,7 @@ GEM
       rake (>= 0.8.7)
       thor (>= 0.18.1, < 2.0)
     rake (10.3.2)
-    rdoc (4.1.1)
-      json (~> 1.4)
+    rdoc (6.3.2)
     redis (3.1.0)
     redis-namespace (1.6.0)
       redis (>= 3.0.4)