Comment 20 for bug 563893

Running Lucid here, upgraded via Upgrade Manager from Karmic. I had been running Thunderbird 2 in Karmic.
Confirming the installed Thunderbird package is 3.0.4+nobinonly-0ubuntu4

I understand - from reading this bug - that Lucid is working around some extensions that are still using "mozilla-thunderbird" calls by having a sym link directory titled ".mozilla-thunderbird" as well as the ".thunderbird" profile directory in ~/home. It also seems to be retaining the "Mozilla-Thunderbird" titles for menus and so forth.
I use either Gnome Do (which calls the Gnome menu link "Mozilla Thunderbird") or Gnome Terminal command "thunderbird" to open Thunderbird 3 and all runs fine.

However, in my home directory, the sym link folder ".mozilla-thunderbird" is echoing the ".thunderbird" folder in a slightly unsettling way:
The profile in "thunderbird" is completely duplicated in ".mozilla-thunderbird". All changes in ".thunderbird" directory are echoed in ".mozilla-thunderbird"; it's not just an empty sym link.
Thus, If I delete the profile in either directory, then simply using manipulating the directories in Nautilus returns the echoing between both directories.

I've not seen this kind of behaviour before and would like to know:
1. Is this expected behaviour for what seems to be a sort of temporary workaround?
2. If not, what sort of approach can I take to troubleshoot the setup?

Gzip doesn't handle archiving this structure - - it turns the ".mozilla-thunderbird" sym link directory into a plain directory and creates a sym link file with no value.
I'm concerned that I may not be able to restore the right structure if it becomes necessary.
Your help would be appreciated.