Partitioning - please not that again

[Ralf Mardorf]

Since partitioning didn't work with FreeBSD 9.0 64bit, I tried PC-BSD
8.2 64bit and partitioning worked.

I had PC-BSD installed on ada0s1, this was the fstab:

/dev/label/rootfs0      /                       ufs             rw,noatime      1       1
/dev/label/swap0        none                    swap            sw              0       0
/dev/label/var0         /var                    ufs             rw,noatime      1       1
/dev/label/usr0         /usr                    ufs             rw,noatime      1       1
procfs                  /proc                   procfs          rw              0       0
linprocfs               /compat/linux/proc      linprocfs       rw              0       0

Plan 9 was to delete the PC-BSD files and than to avoid partitioning,
but simply to install FreeBSD on the existing slice and what ever the
mounted things inside the slice are named.

I startet the FreeBSD installer, chose the shell and then run:

# mount -t ufs /dev/ad0s1 /mnt
# cd /mnt
# rm -r *
# rm -r .*

This does cause the issue I already had before. When I go back to the
installer, for the partition editor I get:

ada0 298 GB MBR
  ada0s1 57 GB freebsd
  ada0s2 240 GB EBR
[snip]

gpart show also doesn't display the 3 ufs and the swap any more.

So I neither can install FreeBSD, nor can I restore the dumped PC-BSD.
Is there no easy to use partitioning tool, comparable to e.g. Linux's
gparted?

How do I have to use the partition editor of the installer?

:(
Ralf