It seemed simple enough, I did an apt-get install thunderbird and left my old .thunderbird directory in place from the FC9 install. When I brought up Thunderbird though, it was as if it was coming up for the first time.
Problem 1 - Thunderbird did not see the old .thunderbird directory
Fix - This was the easy one to spot, apparently the Thunderbird under Ubuntu looks for a .mozilla-thunderbird directory. A quick rename fixed the problem
Next though, I noticed that my calendar didn't work AT ALL. All I saw was the shell of what it would should be, no days were even displayed, no calendars, not even an option to create a new calendar. The calendar info is stored under your profile dir in the .mozilla-thunderbird dir, in a file called storage.sdb. I renamed my storage.sdb file to preserve it, removed the addon for lightning, and reinstalled the addons from the latest .9 version of lightning from http://addons.mozilla.org. After restarting Thunderbird though, I still didn't see a calendar. I didn't want to use the version that shipped with Ubuntu since it was version .7, but it looks like that one works fine. So if you don't care to be using the latest version, then this is a viable workaround, but not the fix I was looking for. As it turns out, the lightning extension I downloaded relies on an older version of libstdc++.
Problem 2 - Empty and non-functional lightning .9
- apt-get install libstdc++5
- Uninstall the lightning addon
- reinstall the lightning addon downloaded from http://addons.mozilla.org
- replace storage.sdb file with your old, saved copy