diff --git a/Doc/lib/libsys.tex b/Doc/lib/libsys.tex
index 8f8b5cc..946ff1d 100644
--- a/Doc/lib/libsys.tex
+++ b/Doc/lib/libsys.tex
@@ -364,6 +364,8 @@
   inserted as a result of \envvar{PYTHONPATH}.
 
   A program is free to modify this list for its own purposes.
+
+  \versionchanged[Unicode strings are no longer ignored.]{2.3}
 \end{datadesc}
 
 \begin{datadesc}{platform}