How is the NFS directory being mounted? Is no-root-squash enabled? If not, root does not have full permissions on files in an NFS mounted share. The NFS server needs to export the file systems with root-squash or no-root-squash which will either block or permit root from accessing files.
You can check this by trying to create a file in the NFS mounted path, and then check the ownership of the file. If root-squash is enabled, then the ownership of the file will probably be "nobody". Typically root-squash is the default.
check with the owner of the NFS share and see if it was exported with root-squash or no-root-squash.
Some links on NFS:
Let us know if this helps...
Ernst F. Graeler
Applications and File Systems