--- a/libidav/davqlparser.h	Fri May 29 09:48:10 2015 +0200
+++ b/libidav/davqlparser.h	Fri May 29 10:15:12 2015 +0200
@@ -314,6 +314,9 @@
 /** A string has been expected. */
 #define DAVQL_ERROR_INVALID_STRING 25
 
+/** The order criterion is invalid (must be an identifier or field index). */
+#define DAVQL_ERROR_INVALID_ORDER_CRITERION 26
+
 /** The depth is invalid. */
 #define DAVQL_ERROR_INVALID_DEPTH 101