diff --git a/src/node.js b/src/node.js
index 052651de0b..e31e000d03 100644
--- a/src/node.js
+++ b/src/node.js
@@ -264,7 +264,7 @@ var eventsModule = createInternalModule('events', function (exports) {
 
   exports.Promise.prototype.addCallback = function (listener) {
     if (this.hasFired === 'success') {
-      return listener.apply(this, this._values);
+      listener.apply(this, this._values);
     }
 
     return this.addListener("success", listener);
diff --git a/test/mjsunit/test-promise.js b/test/mjsunit/test-promise.js
index 2992f93665..149c07e2a0 100644
--- a/test/mjsunit/test-promise.js
+++ b/test/mjsunit/test-promise.js
@@ -24,13 +24,13 @@ a.addErrback(function(error) {
 });
 a.emitSuccess(TEST_VALUE);
 
-a.addCallback(function(value) {
+assert.ok(a.addCallback(function(value) {
   assert.equal(TEST_VALUE, value);
   expectedCallbacks.a2--;
-});
-a.addErrback(function(error) {
+}));
+assert.ok(a.addErrback(function(error) {
   assert.notEqual(TEST_VALUE, error, 'late');
-});
+}));
 
 // Test regular & late errback binding
 var b = new Promise();
@@ -48,10 +48,10 @@ b.addErrback(function(value) {
 // Test late errback binding
 var c = new Promise();
 c.emitError(TEST_VALUE);
-c.addErrback(function(value) {
+assert.ok(c.addErrback(function(value) {
   assert.equal(TEST_VALUE, value);
   expectedCallbacks.c1--;
-});
+}));
 
 // Test errback exceptions
 var d = new Promise();