diff --git a/akka-cluster/src/test/scala/akka/cluster/protobuf/ClusterMessageSerializerSpec.scala b/akka-cluster/src/test/scala/akka/cluster/protobuf/ClusterMessageSerializerSpec.scala
index 47aa7a8cfc..de467cece4 100644
--- a/akka-cluster/src/test/scala/akka/cluster/protobuf/ClusterMessageSerializerSpec.scala
+++ b/akka-cluster/src/test/scala/akka/cluster/protobuf/ClusterMessageSerializerSpec.scala
@@ -50,8 +50,12 @@ class ClusterMessageSerializerSpec extends AkkaSpec {
 
       val node1 = VectorClock.Node("node1")
       val node2 = VectorClock.Node("node2")
-      val g1 = (Gossip(SortedSet(a1, b1, c1, d1)) :+ node1).seen(a1.uniqueAddress).seen(b1.uniqueAddress)
-      val g2 = (g1 :+ node2).seen(a1.uniqueAddress).seen(c1.uniqueAddress)
+      val node3 = VectorClock.Node("node3")
+      val node4 = VectorClock.Node("node4")
+      val g1 = (Gossip(SortedSet(a1, b1, c1, d1)) :+ node1 :+ node2).seen(a1.uniqueAddress).seen(b1.uniqueAddress)
+      val g2 = (g1 :+ node3 :+ node4).seen(a1.uniqueAddress).seen(c1.uniqueAddress)
+      checkSerialization(GossipEnvelope(a1.uniqueAddress, uniqueAddress2, g1))
+      checkSerialization(GossipEnvelope(a1.uniqueAddress, uniqueAddress2, g2))
       checkSerialization(GossipEnvelope(a1.uniqueAddress, uniqueAddress2, g2.copy(overview = g2.overview.copy(unreachable = Set(e1, f1)))))
 
       checkSerialization(InternalClusterAction.Welcome(uniqueAddress, g2))