Index: src/test/java/org/quartz/CronTriggerTest.java
===================================================================
--- src/test/java/org/quartz/CronTriggerTest.java	(revision 703)
+++ src/test/java/org/quartz/CronTriggerTest.java	(working copy)
@@ -19,6 +19,8 @@
 
 import java.text.ParseException;
 
+import java.util.TimeZone;
+
 /**
  * Unit test for CronTrigger.
  */
@@ -44,4 +46,19 @@
         assertEquals( "Cloning failed", trigger, trigger2 );
     }
 
+    // http://jira.opensymphony.com/browse/QUARTZ-579
+    public void testQuartz579() throws ParseException {
+        String tzStr = "PST";
+        if(TimeZone.getDefault().getID().equals(tzStr)) {
+            tzStr = "EST";
+        }
+        TimeZone tz = TimeZone.getTimeZone(tzStr);
+        CronTrigger trigger = new CronTrigger();
+        trigger.setName("Quartz-579");
+        trigger.setGroup(Scheduler.DEFAULT_GROUP);
+        trigger.setTimeZone(tz);
+        trigger.setCronExpression("0 0 12 * * ?");
+        assertEquals( "TimeZone was changed", tz, trigger.getTimeZone() );
+    }
+
 }