Roundcube filter: reply with message doesn't work


I’m trying do make an auto-reply on roundcube (installed on Yunohost), but it doesn’t work. I made a filter with the action “Reply with message” and “move message to”, the filter is working because it moves the messages, but it doesn’t send any response.
I put an issue about it on roundcube, but I got this answer:
“This is not Roundcube issue. The responder need to be configured on imap server side.”

Anybody knows what that mean and how to solve it?

Thanks !

I created an issue on bug tracker :