centos e-mail problem

Sofar I can't get email to work
I spend the whole day trying to fix this,
but can't seem to get it right,

I'm using Centos 5.2 & ISPconfig and my maillog gives the folowing lines :

Jan 22 18:35:01 sofsan postfix/smtpd[16463]: lost connection after CONNECT from localhost.localdomain[127.0.0.1]
Jan 22 18:35:01 sofsan postfix/smtpd[16463]: disconnect from localhost.localdomain[127.0.0.1]
Jan 22 18:40:01 sofsan dovecot: pop3-login: Disconnected: rip=::ffff:127.0.0.1, lip=::ffff:127.0.0.1, secured
Jan 22 18:40:01 sofsan dovecot: imap-login: Disconnected: rip=::ffff:127.0.0.1, lip=::ffff:127.0.0.1, secured
Jan 22 18:40:01 sofsan postfix/smtpd[16665]: connect from localhost.localdomain[127.0.0.1]

and also :

Jan 22 18:10:30 sofsan postfix/smtp[14357]: 7D55A128061: host relay.transip.nl[80.69.67.21] said: 450 4.7.1 Client host rejected: cannot find your hostname, [xx.xx.xx.xxx] (in reply to RCPT TO command)
Jan 22 18:10:31 sofsan postfix/smtp[14357]: 7D55A128061: to=<[email protected]>, relay=relay.transip.nl[80.69.67.19]:25, delay=8100, delays=8099/0.01/0.57/0.02, dsn=4.7.1, status=deferred (host relay.transip.nl[80.69.67.19] said: 450 4.7.1 Client host rejected: cannot find your hostname, [xx.xx.xx.xxx] (in reply to RCPT TO command))

where xx.xx.xx.xxx is the IP-addres of my server


any help is welcome ...

 

Do u have reverse DNS setup correctly ?

 

Make sure that your hostname points to your Ip address.