Index: src/java/org/quartz/JobDetail.java
===================================================================
--- src/java/org/quartz/JobDetail.java	(revision 656)
+++ src/java/org/quartz/JobDetail.java	(working copy)
@@ -495,7 +495,8 @@
         JobDetail copy;
         try {
             copy = (JobDetail) super.clone();
-            copy.jobListeners = SetUtils.orderedSet(new HashSet(jobListeners));
+            copy.jobListeners = SetUtils.orderedSet(new HashSet());
+            copy.jobListeners.addAll(jobListeners);
             if (jobDataMap != null) {
                 copy.jobDataMap = (JobDataMap) jobDataMap.clone();
             }