Configuring SNMPv3 on NXOS

I am struggling with configuring SNMPv3 on a Nexus switch:

stoS01t(config)# snmp-server user **** auth sha ****** priv aes-128 ****** localized auth key should start with 0x[Hex Digits] 

Why does it complain? I am not entering localized key, it's up to the switch to localize the passwords itself. The above command works just fine on an IOS switch (with a slightly different syntax).

And I also have another NXOS switch, that lets me add the same command as above, but doesn't actually create a new user. I also don't see any way to restrict access with ACL, create groups, use "match prefix" to allow specific contexts...

Oh, just found another NXOS switch (same hardware, but slightly different NXOS version) ... and there the above command works fine.