diff --git a/lib/child_process.js b/lib/child_process.js
index 0daa50c7ae..7dc46289eb 100644
--- a/lib/child_process.js
+++ b/lib/child_process.js
@@ -14,10 +14,8 @@ var spawn = exports.spawn = function (path, args /*, options OR env, customFds *
 exports.exec = function (command /*, options, callback */) {
   if (arguments.length < 3) {
     return exports.execFile("/bin/sh", ["-c", command], arguments[1]);
-  } else if (arguments.length < 4) {
-    return exports.execFile("/bin/sh", ["-c", command], arguments[1], arguments[2]);
   } else {
-    return exports.execFile("/bin/sh", ["-c", command], arguments[1], arguments[2], arguments[3]);
+    return exports.execFile("/bin/sh", ["-c", command], arguments[1], arguments[2]);
   }
 };