[Users] Is it possible to attach an ISCSI export to an NFS based Data Center?

Good evening, In 3.0 there was the option to add an ISCSI export to a Data Center using NFS. I could not test the feature, however, as my LUN did not appear in the UI. When I look for this option in the interface of oVirt 3.1 I only find Data/NFS and Export/NFS (I have already an ISO Domain defined, also NFS). Is it this option available in the new version? If so, what are the requirements? Regards, Jose Garcia