diff --git a/Implab.Test/AsyncTests.cs b/Implab.Test/AsyncTests.cs
--- a/Implab.Test/AsyncTests.cs
+++ b/Implab.Test/AsyncTests.cs
@@ -139,6 +139,21 @@ namespace Implab.Test {
         }
 
         [TestMethod]
+        public void ChainFailTest() {
+            var p1 = new Promise<int>();
+
+            var p3 = p1.Chain(x => {
+                var p2 = new Promise<string>();
+                p2.Reject(new Exception("DIE!!!"));
+                return p2;
+            });
+
+            p1.Resolve(100);
+
+            Assert.IsTrue(p3.IsResolved);
+        }
+
+        [TestMethod]
         public void PoolTest() {
             var pid = Thread.CurrentThread.ManagedThreadId;
             var p = AsyncPool.Invoke(() => Thread.CurrentThread.ManagedThreadId);
diff --git a/Implab/Promise.cs b/Implab/Promise.cs
--- a/Implab/Promise.cs
+++ b/Implab/Promise.cs
@@ -893,7 +893,7 @@ namespace Implab {
 
 
         void IPromise.On(Action success, Action<Exception> error, Action cancel) {
-            On(x => success(), error, cancel);
+            On(success != null ? new Action<T>(x => success()) : null, error, cancel);
         }
 
         void IPromise.On(Action success, Action<Exception> error) {