diff --git a/Pmodules/modulefile b/Pmodules/modulefile
index 6b3e91a..c40824d 100644
--- a/Pmodules/modulefile
+++ b/Pmodules/modulefile
@@ -9,6 +9,10 @@ module-help	"
 Pmodules are a hierarchical module environment based on Environment Modules.
 "
 
+#
+# Pmodules >= 1.0.0rc11 set <PackageName>_ROOT
+# But for Pmodules PMODULES_ROOT != PMODULES_DIR and should not be set.
+# 
 set dont-setenv { "PMODULES_ROOT" }
 #
 # It might be that '${PMODULES_ROOT}/Tools/Pmodules/VERSION' is in PATH.