ZFS: What have I done wrong?

I've setup a zpool using Pawel's quickstart guide as a base:

[root_at_hooters ~]# zpool create tank mirror /dev/twed0 /dev/twed1  
mirror /dev/twed2 /dev/twed3 spare /dev/twed4

...a few commands later...

[root_at_hooters ~]# mount | grep tank
tank/ports on /usr/ports (zfs, local)
tank/home on /usr/home (zfs, local)

and zfs_enable="YES" added to rc.conf

However, I don't have a /dev/zvol... am I supposed to have one? Why  
wouldn't I?

Will that allow me to specify my ZFS volumes in fstab so they mount  
at boot time?


Cheers

Philip Murray