diff --git a/gulliver/system/class.bootstrap.php b/gulliver/system/class.bootstrap.php
index beab9374f..a18ce537a 100644
--- a/gulliver/system/class.bootstrap.php
+++ b/gulliver/system/class.bootstrap.php
@@ -3016,6 +3016,10 @@ class Bootstrap
         }
         if (defined('PATH_DATA_SITE') && !defined('PATH_WORKSPACE')) {
             define('PATH_WORKSPACE', PATH_DATA_SITE);
+        }
+        if (defined('PATH_DATA_SITE')) {
+            set_include_path(get_include_path() . PATH_SEPARATOR . PATH_DATA_SITE);
+        } elseif (defined('PATH_WORKSPACE')) {
             set_include_path(get_include_path() . PATH_SEPARATOR . PATH_WORKSPACE);
         }
     }