diff --git a/lib/sandboxed_module.js b/lib/sandboxed_module.js
index 1cd6743fe221cbe91ea92fea3707ed07a8a2ded3..46889217d96d5534a206549ae7bd97100e41c3e4 100644
--- a/lib/sandboxed_module.js
+++ b/lib/sandboxed_module.js
@@ -4,7 +4,7 @@ var Module = require('module');
 var fs = require('fs');
 var vm = require('vm');
 var path = require('path');
-var builtinModules = require('./builtin_modules.json');
+var builtinModules = Module.builtinModules || require('./builtin_modules.json');
 var parent = module.parent;
 var globalOptions = {};
 var registeredBuiltInSourceTransformers = ['coffee'];