SPF/DNS query problem

[TaskSoftware]

I'm experiencing an email issue:
Everytime an external domain that doesn't have spf records on DNS tries to send messages to an account present in Plesk Server, it doesn't arrive and generates a permanent error:
Jun 15 19:36:51 uai1 spf filter[7319]: Failed to query MAIL-FROM: Temporary DNS failure for 'artigraf.com.br'.

Spf tool test:
spfquery_static -ip=187.108.192.52 -sender=whatever@artigraf.com.br -helo=linux.nrserver36.net

It returns:
StartError
Context: Failed to query MAIL-FROM
ErrorCode: (26) DNS lookup failure
Error: Temporary DNS failure for 'artigraf.com.br'.
EndError
(invalid)

I guess this is a bug in my qmail or something like that, because it only happens when receiving from domains without spf.
Is there a way to set on Plesk to accept messages from domains that doesn't have spf records?

Thanks


ps: I posted this on Plesk 9.x before but realized my version is actually my version is 10.3.1

 

[IgorG]

Did you check this KB article? http://kb.parallels.com/en/11152

 

[TaskSoftware]

Thank you IgorG.

" libspf2 performs an SPF check, first it queries the DNS server for an SPF record. If it is not defined, it tries to query for TXT. If both fails, it means there is no SPF for this domain."

Tried and both failed, but it doesn't mean it has a problem. That's okay for a domain not to use SPF records, right? And it has SOA record like it should:

;; AUTHORITY SECTION:
artigraf.com.br. 3600 IN SOA ns1.nrserver.net. noc.nrserver.net. 2011080202 86400 7200 3600000 86400

So, why the messages can't be accepted for delivery ? Am I missing something about this KB article?

Thanks again !