diff --git a/core/expression.class.inc.php b/core/expression.class.inc.php
index 1135cff4c..5df759d7f 100644
--- a/core/expression.class.inc.php
+++ b/core/expression.class.inc.php
@@ -1,4 +1,8 @@
 <?php
 // The file has been moved in iTop 2.2.0+ (revision 3803)
 // Preserve backward compatibility with some external tools (Cf. toolkit)
+
+//  @deprecated since 3.1.0
+DeprecatedCallsLog::NotifyDeprecatedPhpMethod('use core/oql/expression.class.inc.php instead');
+
 require_once(APPROOT.'core/oql/expression.class.inc.php');