I use option -C dns=a,int=a but I get signature verification failed: DNS error or timeout for `grahamcrackers._domainkey.pmailus.com' causing tempfail.
I scanned the source and cfg_dnserr is set but never used. That still does not explain the tempfail because all the output codes should be accept.
I found the tempfail problem was due to a bug in a graylister.
But dk-filter still has a problem with the dns configuration stuff.