diff --git a/product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Base_editUnrestricted.py b/product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Base_editUnrestricted.py
index 3d57767237192d6745358baeaa38287143560f31..26cb8821018853c6fd08a2b8ed95bb30021c6108 100644
--- a/product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Base_editUnrestricted.py
+++ b/product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Base_editUnrestricted.py
@@ -54,7 +54,7 @@ def parseField(f):
     if k.startswith(field_prefix):
       # We only take into account
       # the object attributes
-      k = k[field_prefix_len:]
+      k = k[len(field_prefix):]
       # Form: '' -> ERP5: None
       if v == '':
         v = None