diff --git a/akka-actor/src/main/scala/akka/dataflow/DataFlowVariable.scala b/akka-actor/src/main/scala/akka/dataflow/DataFlowVariable.scala
index 5b72503c43..9becd42e48 100644
--- a/akka-actor/src/main/scala/akka/dataflow/DataFlowVariable.scala
+++ b/akka-actor/src/main/scala/akka/dataflow/DataFlowVariable.scala
@@ -11,7 +11,7 @@ import akka.actor.{Actor, ActorRef}
 import akka.actor.Actor._
 import akka.dispatch.CompletableFuture
 import akka.AkkaException
-import akka.japi.{ Function, SideEffect }
+import akka.japi.{ Function, Effect }
 
 /**
  * Implements Oz-style dataflow (single assignment) variables.
@@ -28,10 +28,10 @@ object DataFlow {
    */
   def thread(body: => Unit): Unit = spawn(body)
 
-  /** Executes the supplied SideEffect in another thread
+  /** Executes the supplied Effect in another thread
    * JavaAPI
    */
-  def thread(body: SideEffect): Unit = spawn(body.apply)
+  def thread(body: Effect): Unit = spawn(body.apply)
 
   /** Executes the supplied function in another thread
    */
diff --git a/akka-actor/src/main/scala/akka/japi/JavaAPI.scala b/akka-actor/src/main/scala/akka/japi/JavaAPI.scala
index 88732a4efc..4454ed117a 100644
--- a/akka-actor/src/main/scala/akka/japi/JavaAPI.scala
+++ b/akka-actor/src/main/scala/akka/japi/JavaAPI.scala
@@ -20,6 +20,13 @@ trait SideEffect {
   def apply: Unit
 }
 
+/**
+ * An executable piece of code that takes no parameters and doesn't return any value.
+ */
+trait Effect {
+  def apply: Unit
+}
+
 /**
  + * A constructor/factory, takes no parameters but creates a new value of type T every call
  + */