diff --git a/product/ERP5Form/ListBox.py b/product/ERP5Form/ListBox.py
index f505988597dbf50ebbd9b84452858b644db98267..6e8232d6fe6e60c32f842a1573a8bd6ed19e410f 100644
--- a/product/ERP5Form/ListBox.py
+++ b/product/ERP5Form/ListBox.py
@@ -2629,8 +2629,8 @@ class ListBoxHTMLRenderer(ListBoxRenderer):
     request = self.request
     field_id = self.getId()
     form = self.getForm()
-    request.set('%s_form_id', %(field_id, form.getId()))
-    request.set('%s_field_id', %(field_id, field_id))
+    request.set('%s_form_id' %field_id, form.getId())
+    request.set('%s_field_id' %field_id, field_id)
     pt = self.getPageTemplate()
     return pt()