grub2 boot root-on-zfs errors

[Beeblebrox]

Massimo:
>> should be written as (hd0,gpt2)/mydataset/@/myfolder/myfile.
Yes, of course - I made the mistake because I was in a hurry writing
the mail. My current & corrected menu choices are:

menuentry "Test1-BSD-ZFS Direct-Boot" {
    insmod zfs
    search -s -l bsds
    set root='hd0,gpt2'
    kfreebsd (hd0,gpt2)/bsds/@/boot/kernel/kernel
    kfreebsd_module_elf (hd0,gpt2)/bsds/@/boot/kernel/opensolaris.ko
    kfreebsd_module_elf (hd0,gpt2)/bsds/@/boot/kernel/zfs.ko
    kfreebsd_module (hd0,gpt2)/bsds/@/boot/zfs/zpool.cache
type=/boot/zfs/zpool.cache
    kfreebsd_loadenv (hd0,gpt2)/bsds/@/boot/device.hints
    set kFreeBSD.vfs.root.mountfrom=zfs:bsds
}
menuentry 'Test2-BSD-ZFS ChainloadBTX' {
    insmod zfs
    set root='hd0,gpt2'
    kfreebsd (hd0,gpt2)/bsds/@/boot/loader
}

Neither of the above entries work. My root zpool is named "bsds" and
the zfs is the same as the root pool. In other words, zfs list =>
bsds   /
bsds/usr   /usr
bsds/var   /var
etc...
I have also tried (unsuccessfully) the above with
    set root='hd0,gpt2'
    kfreebsd /@/boot/loader  OR
    kfreebsd (hd0,gpt2)/@/boot/loader  OR
    kfreebsd (hd0,gpt2)//@/boot/loader
All give "unknown filesystem" message. When I drop to grub
command-propmt, and try:
zfsinfo (hd0,gpt2)  => error: couldn't find a valid label
I did not try the other 2 zfs-related commands because I do not know
how to use them.

Finally, The grub version on the HDD is from Ubuntu-Raring (2.0). I
should and want to re-code grub from the FreeBSD side, but I am
hesitant since I don't want to fail and work to re-install the
bootloader. FreeBSD's grub is also 2.0. The grub-mkconfig command
however, generates a completely different grub.cfg. The currently
installed (ubuntu) grub does not recognize the "t" command and neither
the root ID c2955d0d7dd8618b (no such device)
menuentry 'FreeBSD' --class freebsd --class bsd --class os
$menuentry_id_option 'kfreebsd-simple-c2955d0d7dd8618b' {
tinsmod part_gpt
tinsmod zfs
tif [ x$feature_platform_search_hint = xy ]; then
t  search --no-floppy --fs-uuid --set=root  c2955d0d7dd8618b
telse
t  search --no-floppy --fs-uuid --set=root c2955d0d7dd8618b
tfi
    echo            'Loading kernel of FreeBSD kernel ...'
    kfreebsd        //@/boot/kernel/kernel
    kfreebsd_loadenv    //@/boot/device.hints
tinsmod part_gpt
tinsmod zfs
tif [ x$feature_platform_search_hint = xy ]; then
t  search --no-floppy --fs-uuid --set=root  c2955d0d7dd8618b
telse
t  search --no-floppy --fs-uuid --set=root c2955d0d7dd8618b
tfi
    kfreebsd_module_elf    //@/boot/kernel/opensolaris.ko