"5.7.1 Sender ID (PRA) Not Permitted"?

[Dave McGuire]

Hi folks. One of my customers is relaying mail through my server,
and it's bouncing with a log message that I've never seen before:

Oct 26 14:22:05 mail postfix/smtp[6116]: 363CE1981EC:
to=<***@yyy.zzz>, relay=office.fhsaa.org[72.243.244.90]:25,
delay=3.3, delays=0.22/0/0.49/2.6, dsn=5.7.1, status=bounced (host
office.fhsaa.org[72.243.244.90] said: 550 5.7.1 Sender ID (PRA) Not
Permitted (in reply to end of DATA command))

I'm running Postfix v2.4.0 on that server, and my other outbound
mail is flowing fine. What causes this, and how can I fix it, does
anyone know offhand?

Thanks,
-Dave

[Jay Chandler]

Hi folks. One of my customers is relaying mail through my server, and
relay=office.fhsaa.org[72.243.244.90]:25, delay=3.3,
delays=0.22/0/0.49/2.6, dsn=5.7.1, status=bounced (host
office.fhsaa.org[72.243.244.90] said: 550 5.7.1 Sender ID (PRA) Not
Permitted (in reply to end of DATA command))
I'm running Postfix v2.4.0 on that server, and my other outbound mail
is flowing fine. What causes this, and how can I fix it, does anyone
know offhand?
Thanks,
-Dave

Google is your friend:

http://www.mcse.ms/message2022068.html
They probably haven't configured SenderID properly on their domain.