diff --git a/Gemfile.lock b/Gemfile.lock
index 51648c5a5..aa29c00c1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -283,7 +283,7 @@ GEM
     msgpack (1.7.2)
     multi_json (1.15.0)
     mysql2 (0.5.5)
-    net-imap (0.3.7)
+    net-imap (0.4.0)
       date
       net-protocol
     net-pop (0.1.2)