diff --git a/headers/os/locale/DateFormat.h b/headers/os/locale/DateFormat.h
index 2f9aad01eb..cee04e5543 100644
--- a/headers/os/locale/DateFormat.h
+++ b/headers/os/locale/DateFormat.h
@@ -84,10 +84,19 @@ public:
 									BDate& output);
 
 private:
+			int					_ConvertDayNumberToICU(int day) const;
+
 			U_ICU_NAMESPACE::DateFormat*	_CreateDateFormatter(
 									const BDateFormatStyle style) const;
 
 };
 
 
+inline int
+BDateFormat::_ConvertDayNumberToICU(int day) const
+{
+	return day == 7 ? 1 : day + 1;
+}
+
+
 #endif	// _B_DATE_FORMAT_H_
diff --git a/src/kits/locale/DateFormat.cpp b/src/kits/locale/DateFormat.cpp
index 09fe428656..b70d601915 100644
--- a/src/kits/locale/DateFormat.cpp
+++ b/src/kits/locale/DateFormat.cpp
@@ -366,7 +366,7 @@ BDateFormat::GetDayName(int day, BString& outName,
 	}
 
 	BStringByteSink stringConverter(&outName);
-	names[day].toUTF8(stringConverter);
+	names[_ConvertDayNumberToICU(day)].toUTF8(stringConverter);
 
 	delete simpleFormat;
 	return B_OK;