diff --git a/readme.txt b/readme.txt
index 03541aa30..4c7893b37 100644
--- a/readme.txt
+++ b/readme.txt
@@ -96,7 +96,7 @@
 - CHANGE: chiQGetFullI() and chOQGetFullI() become macros. The queues
   subsystem has been optimized and is no more dependent on semaphores.
   Note that the queues callbacks invocation policy has been slightly
-  changed, see the documentation.
+  changed, see the documentation (backported to 2.2.4).
 
 *** 2.3.2 ***
 - FIX: Fixed invalid BRR() macro in AVR serial driver (bug 3299306)(backported