Description of problem:
Each spamassassin test issues log messages:
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Jun 21 21:26:14 mail spamd[5006]: plugin: eval failed: available_nameservers: No DNS servers available!
Jun 21 21:26:14 mail spamd[5006]: rules: failed to run NO_DNS_FOR_FROM RBL test, skipping:
Jun 21 21:26:14 mail spamd[5006]: (available_nameservers: [...] No DNS servers available!)
Jun 21 21:26:14 mail spamd[5006]: rules: failed to run DNS_FROM_AHBL_RHSBL RBL test, skipping:
Jun 21 21:26:14 mail spamd[5006]: (available_nameservers: [...] No DNS servers available!)
Jun 21 21:26:14 mail spamd[5006]: spf: lookup failed: available_nameservers: No DNS servers available!
Jun 21 21:26:14 mail spamd[5006]: spf: lookup failed: available_nameservers: No DNS servers available!
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Version-Release number of selected component (if applicable):
spamassassin-3.4.0-4.fc20.x86_64

How reproducible:
Always


Actual results:
Log messages as above

Expected results:
RBL tests OK

Additional info:
There is a bug report with a patch upstream:
https://issues.apache.org/SpamAssassin/show_bug.cgi?id=7057
Applied and tested here successfully