Mirroring in FreeBSD 5.3 (gvinum?)

[Roy Badami]

I'm trying to set up a mirrored configuration on FreeBSD 5.3.

I currently have the system running from gvinum on ad0.  I've created
plexes on ad2 to mirror the data onto, but I can't figure out how to
add those plexes to the volumes.

I figure gvinum attach is what I need, but it just gives me 'unknown
command'.

Is there some way to do this with gvinum create?  Any pointers?

Thanks,

    -roy