diff --git a/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala b/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala
index e1ee951248..59e0c40c7e 100644
--- a/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala
+++ b/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala
@@ -112,7 +112,7 @@ abstract class AbstractFSM[S, D] extends FSM[S, D] {
    * called, not only the first one matching.</b>
    */
   final def onTransition(transitionHandler: UnitApply2[S, S]): Unit =
-    onTransition(transitionHandler)
+    onTransition(transitionHandler(_: S, _: S))
 
   /**
    * Set handler which is called upon reception of unhandled messages. Calling