FreeBSD 9.0RC1 to RC2 upgrade

Finally had a little bit of time to deal with my laptop at home. As FreeBSD 9.0RC is out, I thought I'd give this a try by updating from 9.0 RC1.
Normally this works quite easily on FreeBSD by running the freebsd-update utility, but this time it failed.

So to get it work, see here.

In short:

# sed -i '' -e 's/=_/=%@_/' /usr/sbin/freebsd-update

# freebsd-update upgrade -r 9.0-RC2