E: Couldn't find package mdadm, recovery av WD mybook world

user@debian:~$ sudo apt-get install mdadm
Reading package lists... Done
Building dependency tree
Reading state information... Done
Recommended packages:
  exim4 mail-transport-agent
The following NEW packages will be installed:
  mdadm
0 upgraded, 1 newly installed, 0 to remove and 208 not upgraded.
9 not fully installed or removed.
Need to get 275kB of archives.
After this operation, 799kB of additional disk space will be used.
Get:1 http://ftp.us.debian.org lenny/main mdadm 2.6.7.2-3 [275kB]
Fetched 275kB in 2s (120kB/s)
Preconfiguring packages ...
Setting up libbz2-1.0 (1.0.5-1+lenny1) ...
Selecting previously deselected package mdadm.
(Reading database ... 83486 files and directories currently installed.)
Unpacking mdadm (from .../mdadm_2.6.7.2-3_i386.deb) ...
Processing triggers for man-db ...
Setting up libvolume-id0 (0.125-7+lenny3) ...
Setting up udev (0.125-7+lenny3) ...
Installing new version of config file /etc/modprobe.d/blacklist ...
Installing new version of config file /etc/udev/rules.d/50-udev.rules ...
Installing new version of config file /etc/udev/rules.d/60-persistent-input.rule
s ...
Installing new version of config file /etc/udev/rules.d/75-persistent-net-genera
tor.rules ...
Installing new version of config file /etc/udev/rules.d/60-persistent-storage.ru
les ...
Installing new version of config file /etc/udev/rules.d/91-permissions.rules ...
Installing new version of config file /etc/udev/rules.d/80-drivers.rules ...
Installing new version of config file /etc/udev/rules.d/60-persistent-storage-ta
pe.rules ...
update-initramfs is disabled since running on a live CD
Setting up x11-common (1:7.3+20) ...
Setting up libnspr4-0d (4.7.1-5) ...
Setting up libnss3-1d (3.12.3.1-0lenny2) ...
Setting up libperl5.10 (5.10.0-19lenny2) ...
Setting up mdadm (2.6.7.2-3) ...
Generating array device nodes... done.
Generating mdadm.conf... done.
update-initramfs is disabled since running on a live CD
Starting MD monitoring service: mdadm --monitor.
Assembling MD array md1...done (degraded [1/2]).
Assembling MD array md2...done (degraded [1/2]).
Assembling MD array md3...done (degraded [1/2]).
Assembling MD array md4...done (degraded [1/2]).
Generating udev events for MD arrays...done.
Setting up perl-modules (5.10.0-19lenny2) ...
Setting up perl (5.10.0-19lenny2) ...

sudo modprobe md
sudo /dev/md4 b 9 4
sudo apt-get update
sudo apt-get upgrade     *Svarade nej på kernel install
sudo apt-get install mdadm       *svarade all
sudo mkdir /media/xyz
sudo /devmd4 /media/xyz
sudo -R 777 /media/xyz