[FoLUG] server di posta non invia mail

[Masotti Alessandro]

ciao ho un server di posta (postfix)che per certi indirizzi non inoltra 
le email e mi da questo messaggio:

This is the mail system at host vps.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                    The mail system

<xxy@jvskematozzi.com>: host smtp-avas.seeweb.it[217.194.8.28]
     said: 554 5.7.1 <vps>: Helo command rejected: unqualified HELO 
hostname (in
     reply to RCPT TO command)

<xxyxs@jvskematozzi.com>: host smtp-avas.seeweb.it[217.194.8.28] said: 554
     5.7.1 <vps>: Helo command rejected: unqualified HELO hostname (in 
reply to
     RCPT TO command)



Reporting-MTA: dns; vps
X-Postfix-Queue-ID: 3D0A47A44BF
X-Postfix-Sender: rfc822; alessandro.masotti@mastrus.info
Arrival-Date: Tue,  2 Sep 2008 16:50:16 +0200 (CEST)

Final-Recipient: rfc822; xxxc@jvskematozzi.com
Original-Recipient: rfc822;xxxc@jvskematozzi.com
Action: failed
Status: 5.7.1
Remote-MTA: dns; smtp-avas.seeweb.it
Diagnostic-Code: smtp; 554 5.7.1 <vps>: Helo command rejected: 
unqualified HELO
     hostname

Final-Recipient: rfc822; xxxc@jvskematozzi.com
Original-Recipient: rfc822;xxxc@jvskematozzi.com
Action: failed
Status: 5.7.1
Remote-MTA: dns; smtp-avas.seeweb.it
Diagnostic-Code: smtp; 554 5.7.1 <vps>: Helo command rejected: 
unqualified HELO
     hostname




Mi sapete aiutare?

ciao e grazie in anticipo