diff --git a/bin/gen_test b/bin/gen_test
index ad182785..1ab48a27 100755
--- a/bin/gen_test
+++ b/bin/gen_test
@@ -1,4 +1,4 @@
-#!/usr/bin/env ruby -wKU
+#!/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby -wKU
 require 'pathname'
 require 'erb'