diff --git a/mozilla/calendar/modules/nls/nlsstub/inc/unistring.h b/mozilla/calendar/modules/nls/nlsstub/inc/unistring.h
index f78823811af..74902f073ee 100644
--- a/mozilla/calendar/modules/nls/nlsstub/inc/unistring.h
+++ b/mozilla/calendar/modules/nls/nlsstub/inc/unistring.h
@@ -76,6 +76,7 @@ public:
   void extract(TextOffset aOffset, PRInt32 aLength, PRUnichar*aExtractInto) const;
   void extract(TextOffset aOffset, PRInt32 aLength, char* aExtractInto) const;
 
+  UnicodeString& replaceBetween(TextOffset aStart, TextOffset aLimit, const UnicodeString& aString);
 
 public:
   PRUnichar		  operator[](TextOffset	aOffset) const;
diff --git a/mozilla/calendar/modules/nls/nlsstub/src/unistring.cpp b/mozilla/calendar/modules/nls/nlsstub/src/unistring.cpp
index 0b254abf5d9..496c9800695 100644
--- a/mozilla/calendar/modules/nls/nlsstub/src/unistring.cpp
+++ b/mozilla/calendar/modules/nls/nlsstub/src/unistring.cpp
@@ -180,6 +180,11 @@ UnicodeString& UnicodeString::removeBetween(TextOffset aStart, TextOffset aLimit
   return (*this);
 }
 
+UnicodeString& UnicodeString::replaceBetween(TextOffset aStart, TextOffset aLimit, const UnicodeString& aString)
+{
+  return (*this);
+}
+
 PRInt8 UnicodeString::compare(const UnicodeString& aUnicodeString) const
 {
   return (mString.Equals(aUnicodeString.mString));