diff --git a/akka-actor-tests/src/test/scala/akka/dispatch/sysmsg/SystemMessageListSpec.scala b/akka-actor-tests/src/test/scala/akka/dispatch/sysmsg/SystemMessageListSpec.scala
index 395852f32f..7cdd35cc66 100644
--- a/akka-actor-tests/src/test/scala/akka/dispatch/sysmsg/SystemMessageListSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/dispatch/sysmsg/SystemMessageListSpec.scala
@@ -4,11 +4,14 @@
 package akka.dispatch.sysmsg
 
 import akka.testkit.AkkaSpec
+import akka.actor.Props
 
 class SystemMessageListSpec extends AkkaSpec {
   import SystemMessageList.LNil
   import SystemMessageList.ENil
 
+  val child = system.actorOf(Props.empty, "dummy") // need an ActorRef for the Failed msg
+
   "The SystemMessageList value class" must {
 
     "handle empty lists correctly" in {
@@ -18,9 +21,9 @@ class SystemMessageListSpec extends AkkaSpec {
     }
 
     "able to append messages" in {
-      val create0 = Failed(null, null, 0)
-      val create1 = Failed(null, null, 1)
-      val create2 = Failed(null, null, 2)
+      val create0 = Failed(child, null, 0)
+      val create1 = Failed(child, null, 1)
+      val create2 = Failed(child, null, 2)
       ((create0 :: LNil).head eq create0) should ===(true)
       ((create1 :: create0 :: LNil).head eq create1) should ===(true)
       ((create2 :: create1 :: create0 :: LNil).head eq create2) should ===(true)
@@ -31,9 +34,9 @@ class SystemMessageListSpec extends AkkaSpec {
     }
 
     "able to deconstruct head and tail" in {
-      val create0 = Failed(null, null, 0)
-      val create1 = Failed(null, null, 1)
-      val create2 = Failed(null, null, 2)
+      val create0 = Failed(child, null, 0)
+      val create1 = Failed(child, null, 1)
+      val create2 = Failed(child, null, 2)
       val list = create2 :: create1 :: create0 :: LNil
 
       (list.head eq create2) should ===(true)
@@ -43,9 +46,9 @@ class SystemMessageListSpec extends AkkaSpec {
     }
 
     "properly report size and emptyness" in {
-      val create0 = Failed(null, null, 0)
-      val create1 = Failed(null, null, 1)
-      val create2 = Failed(null, null, 2)
+      val create0 = Failed(child, null, 0)
+      val create1 = Failed(child, null, 1)
+      val create2 = Failed(child, null, 2)
       val list = create2 :: create1 :: create0 :: LNil
 
       list.size should ===(3)
@@ -63,9 +66,9 @@ class SystemMessageListSpec extends AkkaSpec {
     }
 
     "properly reverse contents" in {
-      val create0 = Failed(null, null, 0)
-      val create1 = Failed(null, null, 1)
-      val create2 = Failed(null, null, 2)
+      val create0 = Failed(child, null, 0)
+      val create1 = Failed(child, null, 1)
+      val create2 = Failed(child, null, 2)
       val list = create2 :: create1 :: create0 :: LNil
       val listRev: EarliestFirstSystemMessageList = list.reverse
 
@@ -87,12 +90,12 @@ class SystemMessageListSpec extends AkkaSpec {
   "EarliestFirstSystemMessageList" must {
 
     "properly prepend reversed message lists to the front" in {
-      val create0 = Failed(null, null, 0)
-      val create1 = Failed(null, null, 1)
-      val create2 = Failed(null, null, 2)
-      val create3 = Failed(null, null, 3)
-      val create4 = Failed(null, null, 4)
-      val create5 = Failed(null, null, 5)
+      val create0 = Failed(child, null, 0)
+      val create1 = Failed(child, null, 1)
+      val create2 = Failed(child, null, 2)
+      val create3 = Failed(child, null, 3)
+      val create4 = Failed(child, null, 4)
+      val create5 = Failed(child, null, 5)
 
       val fwdList = create3 :: create4 :: create5 :: ENil
       val revList = create2 :: create1 :: create0 :: LNil
diff --git a/akka-actor-tests/src/test/scala/akka/serialization/SerializeSpec.scala b/akka-actor-tests/src/test/scala/akka/serialization/SerializeSpec.scala
index 196c3ff4c1..5133bf1017 100644
--- a/akka-actor-tests/src/test/scala/akka/serialization/SerializeSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/serialization/SerializeSpec.scala
@@ -101,7 +101,10 @@ object SerializationTests {
 
   def mostlyReferenceSystem: ActorSystem = {
     val referenceConf = ConfigFactory.defaultReference()
-    val mostlyReferenceConf = AkkaSpec.testConf.withFallback(referenceConf)
+    // we are checking the old Java serialization formats here
+    val mostlyReferenceConf = ConfigFactory.parseString("""
+      akka.actor.enable-additional-serialization-bindings = off
+      """).withFallback(AkkaSpec.testConf.withFallback(referenceConf))
     ActorSystem("SerializationSystem", mostlyReferenceConf)
   }
 
diff --git a/akka-remote/src/test/scala/akka/remote/transport/SystemMessageDeliveryStressTest.scala b/akka-remote/src/test/scala/akka/remote/transport/SystemMessageDeliveryStressTest.scala
index 6f64d33dbc..9a2e2512cd 100644
--- a/akka-remote/src/test/scala/akka/remote/transport/SystemMessageDeliveryStressTest.scala
+++ b/akka-remote/src/test/scala/akka/remote/transport/SystemMessageDeliveryStressTest.scala
@@ -82,12 +82,13 @@ object SystemMessageDeliveryStressTest {
     var counter = 0
     var burstCounter = 0
     val targetRef = target.asInstanceOf[InternalActorRef]
+    val child = context.actorOf(Props.empty, "failedChild") // need a dummy ActorRef
 
     override def preStart(): Unit = self ! "sendnext"
 
     override def receive = {
       case "sendnext" ⇒
-        targetRef.sendSystemMessage(Failed(null, null, counter))
+        targetRef.sendSystemMessage(Failed(child, null, counter))
         counter += 1
         burstCounter += 1