Sounds like someone is accusing them of being an "open relay"...
Lots of times that is a false positive/reading from getting on a "black list"
unfairly by someone not bothering to un-subscribe from something properly.
Rick Glazier
From: "Sam Franc"
clipped
Here is the complete message:
<[email protected]>:
209.235.147.38 does not like recipient.
Remote host said: 550 5.7.1 <[email protected]>... H:XBL [38.111.133.17] Connections originating from a compromised SPAM
source. Please use your ISP's relay servers.
Giving up on 209.235.147.38.