Comment 3 for bug 369325

I tried successfully the following workaround :
1. download latest thunderbird archive from www.mozilla.com
2. uncompress it to /opt (check the rights) (eg. /opt/thunderbird)
3. create a new shortcut, or modify the existing one in the K menu so that it points to the correct location (eg. '/opt/thunderbird/thunderbird')
4. test your shortcut... thunderbird should start, and create a new profile in your home directory (in my case, it created a .thunderbird directory).
5. close thunderbird (important or the modifications on profiles.ini will be overwritten with old value when it closes).
6. copy old profile (usually under ~/.mozilla-thunderbird/<profile_name> to ~/.thunderbird
7. edit ~/.thunderbird/profiles.ini so that it points to the folder we've just moved on.
8. open thunderbird (you should find back all your mails, configuration, directories, contacts, themes ans extensions)...
... and over all : you should be able to create / edit folders.

I know this doesn't explain why TB froze, neither does it correct it... but at least it helps go on working.