zfs booting feedback

[KOT MATPOCKuH]

Good morning!

I builded world/kernel from stable/9 r244121, installed zfsboot and
zfsloader to disk on Sun Fire V240 with OpenBoot 4.30.4.a.
But boot fails with:
Rebooting with command: boot disk
Boot device: /pci at 1c,600000/scsi at 2/disk at 0,0  File and args:

>> FreeBSD/sparc64 ZFS boot block
    Boot path:   /pci at 1c,600000/scsi at 2/disk at 0,0:a
Consoles: Open Firmware console
ERROR: Last Trap: Division by Zero

Also I tried zfsloader builded from sources @ may 2012:
(same zfsboot, but used zfsloader.old)
Boot device: disk  File and args:

>> FreeBSD/sparc64 ZFS boot block
    Boot path:   /pci at 1c,600000/scsi at 2/disk at 0,0:a
Consoles: Open Firmware console
ofwd_open: Could not open disk1:
ofwd_open: Could not open disk2:
ofwd_open: Could not open disk3:

FreeBSD/sparc64 ZFS enabled bootstrap loader, Revision 1.0
(root at sunspot, Fri Nov  2 08:59:22 MSK 2012)
bootpath="/pci at 1c,600000/scsi at 2/disk at 0,0:a"
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable

ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
ZFS: i/o error - all block copies unavailable
can't load 'kernel'

What's wrong?
Could it a result of crosscompiling?

PS. When writing both zfsloader I got "Invalid argument" message:
# dd if=/boot/zfsloader.old of=/dev/da0a bs=512 oseek=1024
dd: /dev/da0a: Invalid argument
470+1 records in
470+0 records out
240640 bytes transferred in 1.915555 secs (125624 bytes/sec)
Is it okey?

-- 
MATPOCKuH