The original message was received at Fri, 13 May 2011 18:14:15 +0900
from [211.212.219.196]

   ----- The following addresses had permanent fatal errors -----
<oliveriale at tiscali.it>
    (reason: 554 imp-2.mail.tiscali.it  ESMTP server not available if you do not have a 
reverse dns mapping)

이메일을 보내면, 다음과 같이 해서 이메일이 돌아 옵니다.

어떡해야하는 지요?  

 ----- Transcript of session follows -----
... while talking to imp-1.mail.tiscali.it.:
<<< 554 imp-1.mail.tiscali.it  ESMTP server not available if you do not have a reverse dns 
mapping
... while talking to imp-3.mail.tiscali.it.:
>>> QUIT
<<< 554 imp-3.mail.tiscali.it  ESMTP server not available if you do not have a reverse dns 
mapping
... while talking to imp-2.mail.tiscali.it.:
>>> QUIT
<<< 554 imp-2.mail.tiscali.it  ESMTP server not available if you do not have a reverse dns 
mapping
554 5.0.0 Service unavailable