diff --git a/mozilla/calendar/locales/en-US/chrome/calendar/calendar.dtd b/mozilla/calendar/locales/en-US/chrome/calendar/calendar.dtd
index d72d52fad08..6cdb8cfda72 100644
--- a/mozilla/calendar/locales/en-US/chrome/calendar/calendar.dtd
+++ b/mozilla/calendar/locales/en-US/chrome/calendar/calendar.dtd
@@ -115,6 +115,8 @@
 <!ENTITY newevent.repeatdate.tooltip    "Choose a date to end on" >
 <!ENTITY newevent.recurend.warning    "Your repeat-until time is before your end time.">
 <!ENTITY newevent.recurnumberoftimes.warning    "Your must specify the number of times to repeat.">
+<!ENTITY newevent.readonly.item.warning    "This item is in a read-only calendar.  You may not edit it.">
+<!ENTITY newevent.readonly.cal.warning    "This calendar is read-only.">
 <!ENTITY newevent.recurinterval.warning    "Your must specify how often to repeat.">
 <!ENTITY newevent.endtime.tooltip    "Choose an end time for this event" >
 <!ENTITY newevent.starttimeerror.alertmessage "Your event cannot end before it has started. Please fix either the start time or the end time." >
diff --git a/mozilla/calendar/locales/en-US/chrome/calendar/calendar.properties b/mozilla/calendar/locales/en-US/chrome/calendar/calendar.properties
index 5153d6307c1..35b121a870d 100644
--- a/mozilla/calendar/locales/en-US/chrome/calendar/calendar.properties
+++ b/mozilla/calendar/locales/en-US/chrome/calendar/calendar.properties
@@ -204,6 +204,7 @@ otherError=Getting the calendar file failed.\nStatus code: 0x%1$S
 httpPutError=Publishing the calendar file failed.\nStatus code: %1$S: %2$S
 otherPutError=Publishing the calendar file failed.\nStatus code: 0x%1$S
 contentError=This doesn't appear to be a valid file. Here's what I got back from\n%1$S:\nResult: %2$S
+readOnlyMode=There has been an error reading data for calendar: %1$S. It has been placed in read-only mode, since changes to this calendar will likely result in data-loss.  You may change this setting by choosing 'Edit Calendar'.
 
 # Translators, please put the most likely timezone that the people using your
 # locale will be in.  This needs to be a long name taken from