AIX 5.1 install bos.sysmgt.nim.master failed

I was trying to install bos.sysmgt.nim.master on AIX 5.1 with a mounted NFS source, but it failed:

# installp -agXd /nfs/aix51cd1 bos.sysmgt.nim.master
installp: APPLYING software for:
bos.sysmgt.nim.master 5.1.0.50

restore: 0511-123 The volume on /nfs/aix51cd1/installp/ppc/bos.sysmgt is not in backup format.
0503-405 installp: An error occurred while running the restore command.
Use local problem reporting procedures.

installp: CANCELLED software for:
bos.sysmgt.nim.master 5.1.0.50

But I can install it with the CDROM, how can I install with a local file system (or NFS)?

I already added the NFS mount into the /etc/filesystems, also if I copy the source to a local file systems, it also failed with the same "not in backup format" error.

thanks