The above I use on my other pc's/distros but in LMDE it doesn't. It would appear that the LMDE build of thunderbird isn't compatible with Moz/sunbird and the debian iceowl doesn't plugin into thunderbird. A bit of a quandary n'est pas?
The solution is to use Icedove (email client) with iceowl (calendar plugin) although the versions are different and not to use thunderbird until such time as the sunbird plugin becomes available.
Having fun with LMDE, well done