SERVFAIL from validating nameservers for advocaat.pro & advocaten.pro

[Chris Thompson]

DLV records for advocaat.pro & advocaten.pro are among the recent
additions to dlv.isc.org. Using validating recursive nameservers
running BIND 9.5.1-P1 (configured to trust dlv.isc.org), I get SERVFAILs
looking things up in them, although not consistently. This doesn't
happen with non-validating nameservers.

I can't work out what is wrong with them. Does anyone else see the
same effect?

-- 
Chris Thompson
Email: cet1 at cam.ac.uk