Error while sending message to the trisquel-utilisateurs list

Hello! I have an error when I try to send a message to name at domain. I have subscribed to the list and I'm using the address I subscribed with.

The server (correo.trisquel.info) answers: "451 4.3.5 Server configuration problem (in reply to RCPT TO command))" to my mail server after RCPT TO. I also tried to post a message to the trisquel-users list and I have the same error.

The problem is perhaps that I'm using my own ADSL connexion to provide my own mail server and that the Trisquel lists server (correo.trisquel.info) is configured to consider mails from ADSL connexions as spam. If that's the case, could you please remove that discriminant configuration?

Hosting my own mail server (as well as my blog and web site) on my ADSL connexion is an action to keep an open and neutral Internet on which everyone can emit content from its internet access as well as he can access any content. I think that preserving this aspect of the internet is very important !