Index: C:/backyard/activemq/activemq-core/src/main/java/org/apache/activemq/usage/Usage.java
===================================================================
--- C:/backyard/activemq/activemq-core/src/main/java/org/apache/activemq/usage/Usage.java	(revision 585186)
+++ C:/backyard/activemq/activemq-core/src/main/java/org/apache/activemq/usage/Usage.java	(working copy)
@@ -233,7 +233,7 @@
         return (int)((((retrieveUsage() * 100) / limiter.getLimit()) / percentUsageMinDelta) * percentUsageMinDelta);
     }
 
-    private void fireEvent(int oldPercentUsage, int newPercentUsage) {
+    private void fireEvent(final int oldPercentUsage, final int newPercentUsage) {
         if (debug) {
             LOG.debug("Memory usage change.  from: " + oldPercentUsage + ", to: " + newPercentUsage);
         }
@@ -248,11 +248,19 @@
                 callbacks.clear();
             }
         }
-        // Let the listeners know
-        for (Iterator<UsageListener> iter = listeners.iterator(); iter.hasNext();) {
-            UsageListener l = iter.next();
-            l.onUsageChanged(this, oldPercentUsage, newPercentUsage);
-        }
+        // Let the listeners know on a separate thread
+        Runnable listenerNotifier = new Runnable() {
+        
+            public void run() {
+                for (Iterator<UsageListener> iter = listeners.iterator(); iter.hasNext();) {
+                    UsageListener l = iter.next();
+                    l.onUsageChanged(Usage.this, oldPercentUsage, newPercentUsage);
+                }
+            }
+        
+        };
+        //TODO usage a thread pool here?
+        new Thread(listenerNotifier, "Usage.fireEvent").start();
     }
 
     public String getName() {