Is this a blacklisting, or pointing to some other problem?

Customer Support Customer Only Discussion
1

getting this error when using cdosys:
Form could not be processed due to the following errors:

* Email send failed: The server rejected one or more recipient addresses. The server response was: 451  http://www.spamhaus.org/query/bl?ip=64.187.103.248  .

http://cbl.abuseat.org/lookup.cgi?ip=64.187.103.248&.submit=Lookup

2

It isn’t exactly a blacklisting, it is a FQDN mismatch they are talking about

going to check and see if can get that resolved, sometimes they are picky.

3

thanx Stephen, funnily enough its a contact email to my own domain…so i guess i’m blocking myself.
I’ve changed to cdonts for the time being.