diff --git a/lib/repl.js b/lib/repl.js
index 84293e2c4ea..89ac5685f67 100644
--- a/lib/repl.js
+++ b/lib/repl.js
@@ -101,12 +101,12 @@ function REPLServer(prompt, stream, eval, useGlobal, ignoreUndefined) {
 
   var self = this;
 
-  self.useGlobal = useGlobal;
+  self.useGlobal = !!useGlobal;
 
   self.eval = eval || function(code, context, file, cb) {
     var err, result;
     try {
-      if (useGlobal) {
+      if (self.useGlobal) {
         result = vm.runInThisContext(code, file);
       } else {
         result = vm.runInContext(code, context, file);