Index: /home/mmillson/workspace/JBPAPP_4_2_0_GA_CP/server/src/main/org/jboss/ejb/txtimer/EJBTimerServiceImpl.java
===================================================================
--- /home/mmillson/workspace/JBPAPP_4_2_0_GA_CP/server/src/main/org/jboss/ejb/txtimer/EJBTimerServiceImpl.java	(revision 78967)
+++ /home/mmillson/workspace/JBPAPP_4_2_0_GA_CP/server/src/main/org/jboss/ejb/txtimer/EJBTimerServiceImpl.java	(working copy)
@@ -341,17 +341,20 @@
    public void removeTimerService(ObjectName containerId, boolean keepState) throws IllegalStateException
    {
       // remove all timers with the given containerId
-      Iterator it = timerServiceMap.entrySet().iterator();
-      while (it.hasNext())
+      synchronized(timerServiceMap)
       {
-         Map.Entry entry = (Map.Entry)it.next();
-         TimedObjectId key = (TimedObjectId)entry.getKey();
-         TimerServiceImpl timerService = (TimerServiceImpl)entry.getValue();
-         if (containerId.equals(key.getContainerId()))
+         Iterator it = timerServiceMap.entrySet().iterator();
+         while (it.hasNext())
          {
-            log.debug("removeTimerService: " + timerService);
-            timerService.shutdown(keepState);
-            it.remove();
+            Map.Entry entry = (Map.Entry)it.next();
+            TimedObjectId key = (TimedObjectId)entry.getKey();
+            TimerServiceImpl timerService = (TimerServiceImpl)entry.getValue();
+            if (containerId.equals(key.getContainerId()))
+            {
+               log.debug("removeTimerService: " + timerService);
+               timerService.shutdown(keepState);
+               it.remove();
+            }
          }
       }
    }
@@ -380,17 +383,20 @@
       // remove all timers with the given containerId
       else
       {
-         Iterator it = timerServiceMap.entrySet().iterator();
-         while (it.hasNext())
+         synchronized(timerServiceMap)
          {
-            Map.Entry entry = (Map.Entry)it.next();
-            TimedObjectId key = (TimedObjectId)entry.getKey();
-            TimerServiceImpl timerService = (TimerServiceImpl)entry.getValue();
-            if (containerId.equals(key.getContainerId()))
+            Iterator it = timerServiceMap.entrySet().iterator();
+            while (it.hasNext())
             {
-               log.debug("removeTimerService: " + timerService);
-               timerService.shutdown(keepState);
-               it.remove();
+               Map.Entry entry = (Map.Entry)it.next();
+               TimedObjectId key = (TimedObjectId)entry.getKey();
+               TimerServiceImpl timerService = (TimerServiceImpl)entry.getValue();
+               if (containerId.equals(key.getContainerId()))
+               {
+                  log.debug("removeTimerService: " + timerService);
+                  timerService.shutdown(keepState);
+                  it.remove();
+               }
             }
          }
       }      
@@ -447,24 +453,26 @@
    public String listTimers()
    {
       StringBuffer retBuffer = new StringBuffer();
-      Iterator it = timerServiceMap.entrySet().iterator();
-      while (it.hasNext())
+      synchronized(timerServiceMap)
       {
-         Map.Entry entry = (Map.Entry)it.next();
-         TimedObjectId timedObjectId = (TimedObjectId)entry.getKey();
-         retBuffer.append(timedObjectId + "\n");
-
-         TimerServiceImpl timerService = (TimerServiceImpl)entry.getValue();
-         Collection col = timerService.getAllTimers();
-         for (Iterator iterator = col.iterator(); iterator.hasNext();)
+         Iterator it = timerServiceMap.entrySet().iterator();
+         while (it.hasNext())
          {
-            TimerImpl timer = (TimerImpl)iterator.next();
-            TimerHandleImpl handle = new TimerHandleImpl(timer);
-            retBuffer.append("   handle: " + handle + "\n");
-            retBuffer.append("      " + timer + "\n");
+            Map.Entry entry = (Map.Entry)it.next();
+            TimedObjectId timedObjectId = (TimedObjectId)entry.getKey();
+            retBuffer.append(timedObjectId + "\n");
+
+            TimerServiceImpl timerService = (TimerServiceImpl)entry.getValue();
+            Collection col = timerService.getAllTimers();
+            for (Iterator iterator = col.iterator(); iterator.hasNext();)
+            {
+               TimerImpl timer = (TimerImpl)iterator.next();
+               TimerHandleImpl handle = new TimerHandleImpl(timer);
+               retBuffer.append("   handle: " + handle + "\n");
+               retBuffer.append("      " + timer + "\n");
+            }
          }
       }
       return retBuffer.toString();
-   }
- 
+   } 
 }