FreeBSD ZFS system

[Dick Hoogendijk]

OK, it works very well. Installing a ZFS FreeBSD system with an ufs 
/boot is very very easy using the PC-BSD DVD.
However, I have one question:

I'd like to install FreeBSD (pcbsd) on a (zfs) mirror
In OpenSolaris you can install directly to the zfs mirror, but how's 
this in this situation> After all, an UFS partitin is also created. How 
can I get the equivalent of an OpenSolaris mirrored install for a 
FreeBSD system?

Hope I phrased the question clearly enough.