The 5.4 SDK Perl documentation (check doc/perldoc/OntapiClusterAPI.html under where you've extracted your SDK) references an "rquotad-port" parameter to the "nfs-service-modify" API in the vserver API family.
It's also an output for the nfs-serivce-get-iter API.
Hope this helps.
Bob Greenwald
Lead Storage Engineer
Huron Consulting Group
NCDA CDoT | NCIE-SAN CDoT