Service call failed in json-prolog while querying an owl file in Cram

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Hi,

I started a roslisp node in cram and have json-prolog query services (i can see

/json_prolog/finish
/json_prolog/next_solution
/json_prolog/query
/json_prolog/simple_query

when i do "rosservice list").

Also by typing (json-prolog:check-connection) i receive T. so i assume that everything set up properly.

problem is when i try any query like

(json-prolog:prolog '("rdf_has" ?owlname "http://knowrob.org/kb/srdl2-comp.owl#urdfName" ("literal" ?var)))

i receive

Prolog query failed: Got error: The value
             |'["rdf_has",{"variable":"OWLNAME"},"http://knowrob.org/kb/srdl2-comp.owl#urdfName",{"term":["literal",{"variable":"VAR"}]}]'|
           is not of type
             LIST..

also i have

[(JSON-PROLOG) WARN] 1505226166.532: Service call failed. 
[(JSON-PROLOG) WARN] 1505226166.532: Retrying...

Thanks