diff --git a/addons/website_forum/models/forum.py b/addons/website_forum/models/forum.py
index 4e0ba27fa61..9f17605b690 100644
--- a/addons/website_forum/models/forum.py
+++ b/addons/website_forum/models/forum.py
@@ -720,7 +720,8 @@ class Post(models.Model):
             'subtype_xmlid': 'mail.mt_comment',
             'date': self.create_date,
         }
-        new_message = question.with_context(mail_create_nosubscribe=True).message_post(**values)
+        # done with the author user to have create_uid correctly set
+        new_message = question.with_user(self_sudo.create_uid.id).with_context(mail_create_nosubscribe=True).message_post(**values)
 
         # unlink the original answer, using SUPERUSER_ID to avoid karma issues
         self.sudo().unlink()