> Previously we have not been able to have ZFS support due to it being
> licensed under the CDDL and the kernel under the GPL.
>
> Sun have contributed ZFS support to GRUB under the GPL license. We
> could now use that code to implement support for ZFS in the Linux
> kernel.
>
>
http://blogs.sun.com/darren/entry/zfs_under_gplv2_already_exists