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diff --git a/test/disabled/presentation/akka/src/akka/util/ListenerManagement.scala b/test/disabled/presentation/akka/src/akka/util/ListenerManagement.scala
new file mode 100644
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+++ b/test/disabled/presentation/akka/src/akka/util/ListenerManagement.scala
@@ -0,0 +1,81 @@
+/**
+ * Copyright (C) 2009-2011 Scalable Solutions AB <http://scalablesolutions.se>
+ */
+
+package akka.util
+
+import java.util.concurrent.ConcurrentSkipListSet
+import akka.actor.{ ActorInitializationException, ActorRef }
+
+/**
+ * A manager for listener actors. Intended for mixin by observables.
+ *
+ * @author Martin Krasser
+ */
+trait ListenerManagement {
+
+  private val listeners = new ConcurrentSkipListSet[ActorRef]
+
+  /**
+   * Specifies whether listeners should be started when added and stopped when removed or not
+   */
+  protected def manageLifeCycleOfListeners: Boolean = true
+
+  /**
+   * Adds the <code>listener</code> this this registry's listener list.
+   * The <code>listener</code> is started by this method if manageLifeCycleOfListeners yields true.
+   */
+  def addListener(listener: ActorRef) {
+    if (manageLifeCycleOfListeners) listener.start()
+    listeners add listener
+  }
+
+  /**
+   * Removes the <code>listener</code> this this registry's listener list.
+   * The <code>listener</code> is stopped by this method if manageLifeCycleOfListeners yields true.
+   */
+  def removeListener(listener: ActorRef) {
+    listeners remove listener
+    if (manageLifeCycleOfListeners) listener.stop()
+  }
+
+  /*
+   * Returns whether there are any listeners currently
+   */
+  def hasListeners: Boolean = !listeners.isEmpty
+
+  /**
+   * Checks if a specific listener is registered. ActorInitializationException leads to removal of listener if that
+   * one isShutdown.
+   */
+  def hasListener(listener: ActorRef): Boolean = listeners.contains(listener)
+
+  protected[akka] def notifyListeners(message: => Any) {
+    if (hasListeners) {
+      val msg = message
+      val iterator = listeners.iterator
+      while (iterator.hasNext) {
+        val listener = iterator.next
+        // Uncomment if those exceptions are so frequent as to bottleneck
+        // if (listener.isShutdown) iterator.remove() else
+        try {
+          listener ! msg
+        } catch {
+          case e: ActorInitializationException =>
+            if (listener.isShutdown) iterator.remove()
+        }
+      }
+    }
+  }
+
+  /**
+   * Execute <code>f</code> with each listener as argument. ActorInitializationException is not handled.
+   */
+  protected[akka] def foreachListener(f: (ActorRef) => Unit) {
+    val iterator = listeners.iterator
+    while (iterator.hasNext) {
+      val listener = iterator.next
+      if (listener.isRunning) f(listener)
+    }
+  }
+}