--- a/jdk/src/share/classes/java/time/chrono/MinguoDate.java	Fri Aug 30 11:43:57 2013 +0100
+++ b/jdk/src/share/classes/java/time/chrono/MinguoDate.java	Wed Sep 04 15:18:54 2013 +0100
@@ -421,8 +421,9 @@
     }
 
     @Override
-    public Period until(ChronoLocalDate endDate) {
-        return isoDate.until(endDate);
+    public ChronoPeriod until(ChronoLocalDate endDate) {
+        Period period = isoDate.until(endDate);
+        return getChronology().period(period.getYears(), period.getMonths(), period.getDays());
     }
 
     @Override  // override for performance