I'm running into a problem with Windows 7 Client for NFS interacting with IBM z/OS (MVS). The client is issuing a READDIRPLUS and getting a response of NFS3ERR_NOTSUPP. The client retries the request in a loop. Note that I was able, prior to trying to view a "directory" from MVS to open a specific file. The z/OS NFS V3 protocol for conventional MVS data sets is documented as not supporting the READDIRPLUS procedure (page 44 of z/OS V1R11.0 Network File System Guide and Reference). Clearly this is annoying but the real problem is that windows goes into a loop rather than recognizing the error and either falling back to a V2 protocol paradigm or at least not looking for the extended file attributes. I found that the client was in a loop by running a trace with Wireshark. Unfortunately I didn't in fact save the trace. I can reproduce if necessary.

Is anyone out there? Anyone connecting Windows XP/7 to a mainframe beyond telnet / ftp?