Postfix vs gmail(lehet mas is)

Sziasztok!

Server IP cim valtas utan nem mennek kifele levelek(marmint tuloldal vissza dobja)
DNS, rDNS tobbszor ellenorizve, SPF szint ugy.

This is the mail system at host xxxx.


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

: host gmail-smtp-in.l.google.com[74.125.39.27] said:
550-5.7.1 [xxxxx] The IP you're using to send mail is not authorized
to 550-5.7.1 send email directly to our servers. Please use the SMTP relay
at your 550-5.7.1 service provider instead. Learn more at
550 5.7.1 http://mail.google.com/support/bin/answer.py?answer=10336
n3si910207fam.77 (in reply to end of DATA command)

Google link nem ír semmi konkrétumot. :(

Valakinek van ötlete mi lehet a gond? Mit nézzek még meg?

Köszi Zsirmo