[Thanks!] all round for the help.

Tried the suggestions, heres the result:-

BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

~ $ root


BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

Nokia-N900:~# apt-get remove libqtm-12-contacts
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run `apt-get -f install' to correct these:
The following packages have unmet dependencies:
libqtm-12-versit: Depends: libqtm-12-contacts but it is not going to be installed
mbarcode-plugin-qrcode: Depends: libqtm-12-contacts but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).
Nokia-N900:~# dpkg --configure -a
Nokia-N900:~# dpkg --clear-avail
Nokia-N900:~# apt-get update
Get:1 http://repository.maemo.org fremantle-1.3 Release.gpg [489B]
Ign http://repository.maemo.org fremantle-1.3/free Translation-en_GB
Ign http://repository.maemo.org fremantle-1.3/non-free Translation-en_GB
Get:2 http://repository.maemo.org fremantle Release.gpg [197B]
Ign http://repository.maemo.org fremantle/free Translation-en_GB
Ign http://repository.maemo.org fremantle/non-free Translation-en_GB
Get:3 http://repository.maemo.org fremantle Release.gpg [489B]
Get:4 https://downloads.maemo.nokia.com ./ Release.gpg [198B]
Ign http://repository.maemo.org fremantle/free Translation-en_GB
Ign http://repository.maemo.org fremantle/non-free Translation-en_GB
Get:5 http://repository.maemo.org fremantle Release.gpg [489B]
Ign http://repository.maemo.org fremantle/free Translation-en_GB
Ign http://repository.maemo.org fremantle/non-free Translation-en_GB
Hit http://repository.maemo.org fremantle-1.3 Release
Ign https://downloads.maemo.nokia.com ./ Translation-en_GB
Hit http://repository.maemo.org fremantle Release
Get:6 http://repository.maemo.org fremantle Release [7953B]
Get:7 https://downloads.maemo.nokia.com ./ Release.gpg [198B]
Hit http://repository.maemo.org fremantle Release
Ign https://downloads.maemo.nokia.com ./ Translation-en_GB
Ign http://repository.maemo.org fremantle-1.3/free Packages/DiffIndex
Ign http://repository.maemo.org fremantle-1.3/non-free Packages/DiffIndex
Ign http://repository.maemo.org fremantle/free Packages/DiffIndex
Ign http://repository.maemo.org fremantle/non-free Packages/DiffIndex
Ign http://repository.maemo.org fremantle/free Packages/DiffIndex
Get:8 https://downloads.maemo.nokia.com ./ Release.gpg [481B]
Ign http://repository.maemo.org fremantle/non-free Packages/DiffIndex
Ign http://repository.maemo.org fremantle/free Packages/DiffIndex
Ign http://repository.maemo.org fremantle/non-free Packages/DiffIndex
Ign https://downloads.maemo.nokia.com ./ Translation-en_GB
Hit http://repository.maemo.org fremantle-1.3/free Packages
Hit http://repository.maemo.org fremantle-1.3/non-free Packages
Hit http://repository.maemo.org fremantle/free Packages
Hit https://downloads.maemo.nokia.com ./ Release
Hit https://downloads.maemo.nokia.com ./ Release
Hit http://repository.maemo.org fremantle/non-free Packages
Hit https://downloads.maemo.nokia.com ./ Release
Hit http://repository.maemo.org fremantle/free Packages
Get:9 http://repository.maemo.org fremantle/non-free Packages [271kB]
Hit http://repository.maemo.org fremantle/free Packages
Ign https://downloads.maemo.nokia.com ./ Packages/DiffIndex
Hit http://repository.maemo.org fremantle/non-free Packages
Ign https://downloads.maemo.nokia.com ./ Packages/DiffIndex
Get:10 https://downloads.maemo.nokia.com ./ Release [507B]
Hit https://downloads.maemo.nokia.com ./ Packages
Ign https://downloads.maemo.nokia.com ./ Release
Hit https://downloads.maemo.nokia.com ./ Packages
Ign https://downloads.maemo.nokia.com ./ Packages/DiffIndex
Hit https://downloads.maemo.nokia.com ./ Packages
Fetched 282kB in 10s (26.8kB/s)
Reading package lists... Done
W: GPG error: https://downloads.maemo.nokia.com ./ Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY ADB4438160A655EF
W: You may want to run apt-get update to correct these problems
Nokia-N900:~# apt-get -f install
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following extra packages will be installed:
libqtm-12
The following NEW packages will be installed:
libqtm-12
0 upgraded, 1 newly installed, 0 to remove and 3 not upgraded.
1 not fully installed or removed.
Need to get 0B/4643kB of archives.
After this operation, 17.8MB of additional disk space will be used.
Do you want to continue [Y/n]? y
(Reading database ... 31742 files and directories currently installed.)
Unpacking libqtm-12 (from .../libqtm-12_1%3a1.2.0+git20111104-0nd~fremantle2_armel.deb) ...
dpkg: error processing /var/cache/apt/archives/libqtm-12_1%3a1.2.0+git20111104-0nd~fremantle2_armel.deb (--unpack):
trying to overwrite `/opt/qtm12/plugins/versit/libqtversit_vcardpreserver.so', which is also in package libqtm-12-versit
dpkg-deb: subprocess paste killed by signal (Broken pipe)
Errors were encountered while processing:
/var/cache/apt/archives/libqtm-12_1%3a1.2.0+git20111104-0nd~fremantle2_armel.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
Nokia-N900:~#