Live upgrade issue with ZFS Root

I have created a solaris10 update9 zfs root flash archive for sun4v environment which i 'm tryin to use for upgrading solaris10 update8 zfs root based server using live upgrade.

following is my current system status


lustatus
Boot Environment Is Active Active Can Copy
Name Complete Now On Reboot Delete Status
-------------------------- -------- ------ --------- ------ ----------
zfsBE yes yes yes no -
zfsBEu9 yes no no yes -


when i try to upgrade the with luupgrade i get following error


luupgrade -f -n zfsBEu9 -s /mnt -a /flash/zfsBEu9.flar

63521 blocks
miniroot filesystem is <lofs>
Mounting miniroot at </mnt/S
Validating the contents of the media </mnt>.
The media is a standard Solaris media.
Validating the contents of the miniroot </mnt/S.
Locating the flash install program.
Checking for existence of previously scheduled Live Upgrade requests.
Constructing flash profile to use.
Creating flash profile for BE <zfsBEu9>.
Performing the operating system flash install of the BE <zfsBEu9>.
CAUTION: Interrupting this process may leave the boot environment unstable or unbootable.
ERROR: The flash install failed; pfinstall returned these diagnostics:

ERROR: Field 2 - Invalid disk name (zfsBEu9)
The Solaris flash install of the BE <zfsBEu9> failed.

What could be the reason for this .. is there anything i 'm not doin k ?