diff --git a/useradmin/src/main/java/org/apache/felix/useradmin/impl/UserAdminEventDispatcherImpl.java b/useradmin/src/main/java/org/apache/felix/useradmin/impl/UserAdminEventDispatcherImpl.java
index fcd1757..e27dd61 100644
--- a/useradmin/src/main/java/org/apache/felix/useradmin/impl/UserAdminEventDispatcherImpl.java
+++ b/useradmin/src/main/java/org/apache/felix/useradmin/impl/UserAdminEventDispatcherImpl.java
@@ -158,10 +158,11 @@
      * Closing UserAdminTrackers and putting running state to false.
      * @see org.apache.felix.useradmin.impl.UserAdminEventDispatcher#close()
      */
-    public void close()
+    public synchronized void close()
     {
         userAdminTrackerListener.close();
-        running = true;
+        running = false;
+        notifyAll();
     }
 
     /**