Libranet3 Package Install Problem

[lurch]

I am running LN3 which I upgraded to Sarge using DVDs. Prior to that I did some upgrading via Backports but have since commented out Backports in the sources.list file. Everything was going well until I decided to reinstall Digikam and its plugins. The error message I received via apt-get and Synaptic is as follows:

Package digikam is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package digikam has no installation candidate

My sources.list file is:

deb cdrom:[Debian GNU/Linux 3.1 r2 _Sarge_ - Official i386 Binary-2 (20060419)]/ unstable contrib main
deb cdrom:[Debian GNU/Linux 3.1 r2 _Sarge_ - Official i386 Binary-1 (20060419)]/ unstable contrib main

##SARGE

deb http://ftp.au.debian.org/debian/ sarge main contrib non-free
# deb-src http://ftp.au.debian.org/debian/ sarge main contrib non-free

deb http://security.debian.org/debian-security/ sarge/updates main contrib non-free
# deb-src http://security.debian.org/debian-security/ sarge/updates main contrib non-free

##MARILLAT NON-FREE MULTIMEDIA

deb http://www.debian-multimedia.org/ sarge main

My preferences file is:

Explanation:
Package: *
Pin: release o=Debian,a=sarge
Pin-Priority: 900

Package: *
Pin: origin www.debian-multimedia.org
Pin-Priority: 500

Package: *
Pin: release o=Debian
Pin-Priority: -10

I'm not sure how to correct the problem. Any advice would be much appreciated.

Thanks.
Phillip.

[lurch]

I've solved the problem without really knowing why. There was some conflict involving my preferences file. I removed it, then did an apt-get update, then apt-get dist-upgrade. Seven security packages were than upgraded that did not upgrade while the preferences file existed. I was then able to reinstall digikam and some other applications.