Stephen and Stephane,
I'm seeing the same error. When I try to enter the command that is failing to a 10GigE port on my X460G2-48p-10G4, I get the following.
Slot-1 LabNet_Core.2 # conf port 1:51 auto on
Error: Speed has to be specified on port 1:51
This is to be expected when you run that command on a 10GigE port, since auto negotiation isn't supported on our 10GigE ports.
Slot-1 LabNet_Core.4 # conf port 1:51 auto on speed 10000 duplex full
Error: Auto negotiation is not supported on port 1:51 at 10G speed
I wonder if this is a ZTP+ bug.
Regards, Scott