[CentOS] Sendmail problem

Wed Apr 12 00:23:55 UTC 2006
Thomas E Dukes <edukes at alltel.net>

Here'sanother bounce email:

The original message was received at Tue, 11 Apr 2006 19:16:44 -0400 from
localhost.localdomain [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
<xxxxxx at comcast.net>
    (reason: 521-EHLO/HELO from sender 71.31.91.127 does not map to
localhost.localdomain in DNS)

   ----- Transcript of session follows ----- ... while talking to
gateway-s.comcast.net.:
>>> MAIL From:<apache at localhost.localdomain> SIZE=2176
<<< 521-EHLO/HELO from sender 71.31.91.127 does not map to
localhost.localdomain in DNS <<< 521-sending machine name must be provided
as a fully <<< 521-qualified domain via EHLO/HELO command.
<<< 521-see section 4.1.1.1 and 4.1.4 of RFC 2821 <<< 521 521: Comcast
requires that all mail servers must have a PTR record with a valid Reverse
DNS entry. Currently your mailserver does not fill that requirement. For
more information, refer to:
http://www.comcast.net/help/faq/index.jsp?faq=Email118405
554 5.0.0 Service unavailable