Problems with Icedove on Squeeze and Trinity 3.5.13 with Slávek's repository added

Hello, everybody :-) This is a fresh installation and I am still setting it up. All seemed to be well until I tried to launch Icedove. A small icon followed the mouse, no other result. I purged and reinstalled a couple of times, still no luck. So I purged, removed some gunk (files an directories) that was still there and installed the mozilla.debian version of Icedove. Still the same. This time I thought to keep some of the error messages, where there were any. They are below, in the order in which I did them: not very logical I'm afraid. Before I purge and install from source, possibly/probably with the same result, can anyone see what the problem is, and how I should resolve it? Lisi root@Squeeze:/home/john# aptitude install -t squeeze-backports icedove The following NEW packages will be installed: icedove 0 packages upgraded, 1 newly installed, 0 to remove and 79 not upgraded. Need to get 13.4 MB of archives. After unpacking 41.7 MB will be used. Get:1 http://backports.debian.org/debian-backports/ squeeze-backports/main icedove amd64 3.1.16-1~bpo60+1 [13.4 MB] Fetched 13.4 MB in 18s (729 kB/s) Selecting previously deselected package icedove. (Reading database ... 120924 files and directories currently installed.) Unpacking icedove (from .../icedove_3.1.16-1~bpo60+1_amd64.deb) ... Processing triggers for hicolor-icon-theme ... Processing triggers for man-db ... Setting up icedove (3.1.16-1~bpo60+1) ... root@Squeeze:/home/john# icedove /usr/lib/icedove/icedove-bin: symbol lookup error: /usr/lib/icedove/components/libimgicon.so: undefined symbol: NS_GetServiceManager root@Squeeze:/home/john# which icedove /usr/bin/icedove root@Squeeze:/home/john# /usr/bin/icedove /usr/lib/icedove/icedove-bin: symbol lookup error: /usr/lib/icedove/components/libimgicon.so: undefined symbol: NS_GetServiceManager root@Squeeze:/home/john# john@Squeeze:~$ icedove /usr/lib/icedove/icedove-bin: symbol lookup error: /usr/lib/icedove/components/libimgicon.so: undefined symbol: NS_GetServiceManager john@Squeeze:~$ which icedove /usr/bin/icedove john@Squeeze:~$ whereis icedove icedove: /usr/bin/icedove /etc/icedove /usr/lib/icedove /usr/lib64/icedove /usr/share/icedove /usr/share/man/man1/icedove.1.gz john@Squeeze:~$ /usr/bin/icedove #/usr/lib/icedove/icedove-bin: symbol lookup error: /usr/lib/icedove/components/libimgicon.so: undefined symbol: NS_GetServiceManager john@Squeeze:~$ #