How to boot multiple FreeBSD systems (GPT, ZFS)?

[Jens Schweikhardt]

hello, world\n

in the good old days of MBR the FreeBSD bootblock would let me
select one of several root partitions to boot from with a prompt like
F1 FreeBSD
F2 FreeBSD
F3 FreeBSD

Those times are gone; the new kids on the block are GPT partitioned
disks and ZFS. I've read many man pages and articles on the net on using
gpart, gptzfsboot, bios-boot partition, separate mini boot partition,
setting up a root on ZFS system, and others. The part where I'm having
difficulties is: which program lets me do the selection?
***No, I can't use grub or grub2.***

Can anyone outline how to partition and install a system that lets
me select at boot time which of several ZFS root file systems to boot?
I'm fine with the big picture and can figure out the details myself.

Regards,

	Jens
-- 
Jens Schweikhardt http://www.schweikhardt.net/
SIGSIG -- signature too long (core dumped)