diff --git a/src/sampleconf/fields b/src/sampleconf/fields
index a56d4910..e7dc7bf3 100644
--- a/src/sampleconf/fields
+++ b/src/sampleconf/fields
@@ -42,7 +42,10 @@ keywords = K
 # add your own to search for fields produced by the filters and not handled
 # by default. 
 # Some values are internally reserved by recoll: 
-#   XP (for path elements).
+#   XP (for path elements), XXST, XXND
+# Using XX was not a good idea. 
+# I hereby commit to not using XY for Recoll:
+# *** USE XY for beginning your local prefixes ***
 ext = XE
 filename = XSFN
 recipient = XTO