diff --git a/mozilla/calendar/locales/en-US/chrome/calendar/dateFormat.properties b/mozilla/calendar/locales/en-US/chrome/calendar/dateFormat.properties
index a407a688130..14273d4dfd4 100644
--- a/mozilla/calendar/locales/en-US/chrome/calendar/dateFormat.properties
+++ b/mozilla/calendar/locales/en-US/chrome/calendar/dateFormat.properties
@@ -79,5 +79,14 @@ day.5.Mmm=Thu
 day.6.Mmm=Fri
 day.7.Mmm=Sat
 
+# Can someone tell me why were not counting from zero?
+day.1.short=S
+day.2.short=M
+day.3.short=T
+day.4.short=W
+day.5.short=T
+day.6.short=F
+day.7.short=S
+
 am-string=AM
 pm-string=PM