Hi,
>....
>
> > >The curious thing is that if I put in the FROM field an external
> > >address, qmail is able to send-out
> > >the error message whitout any problem!!!
>
>701? permissions even an issue?
I have given thig right for the maildirs to have much security for it.
>name was not resolved...
have a look in the file where the mailusers are defined.
If you have trouble to get the hostname of your mailserver have
a look into your dns-database. In this case there must be a problem
in the forward- and/or reverselookup.
One other you should check is /var/qmail/control/rcpthost, especially.
Here you should set libero.it.
Additionally you should look in the lwq for local delivery.
Regards,
Ruprecht