Asked for password change from rescue system on pogoplug pink (no replies)

Hi

one could say "Huston, we've got a problem..."

I installed the rescue system (http://forum.doozan.com/read.php?4,7915,7915) on a pogoplug (pink one) and I could boot in it without problems. Then I changed the password and tried to install Wheezy.
Disabling perl caused the first problem: even after chmod -x /usr/bin/perl perl was still there (I remopunted rw before and afterwards changed to ro again).

I tried to rename perl to perl.bak (which worked - perl was not in the path anymore), but I got the following error:

...
This filesystem will be automatically checked every 21 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.
Setting up swapspace version 1, size = 2048090 kB


# Starting debootstrap installation
E: unrecognized or invalid option --no-check-gpg
debootstrap failed.
See /tmp/debian/debootstrap/debootstrap.log for more information.
rescue:/tmp

So I changed it back and rebooted, because I thought that it might work afterwards. But now I am facing the following problem:

When logging in via ssh, I am asked to change the password, which obviously does not work as / is mounted ro. But I can not mount it as rw, as I can not login via ssh.

$ ssh root@pogoplug
root@pogoplug's password: 
WARNING: Your password has expired.
You must change your password now and login again!
Changing password for root
New password: 
Retype password: 
passwd: /etc/passwd: Read-only file system
passwd: can't update password file /etc/passwd
Connection to pogoplug closed.
$

I don't have a bootable partition on my external hdd, as the installer formated it already.

Any suggestions?

Rainer