[Dovecot] deliver configuration

Hi.,

I am trying to configure Virtual Users. Whenever I use: "virtual_transport = dovecot" I get:

deliver(user_at_domain): net_connect(/usr/local/var/run/dovecot/auth-master) failed: No such file or directory

But it works when I use: "virtual_transport = virtual"

What am I doing wrong?

Thank you !