diff --git a/Gemfile.lock b/Gemfile.lock
index eed2c67..3919241 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -3,7 +3,8 @@ GEM
   specs:
     json (1.8.1)
     rake (10.3.2)
-    rscons (1.4.3)
+    rscons (1.5.0)
+      json (~> 1.0)
 
 PLATFORMS
   ruby