Rated 1 out of 5 stars

Unusable. Asks EVERYTIME upon startup for ALL passwords stored in the login keychain (I have tons of it). It should ask only for those that it needs, especially that there is no option to 'Deny Always' only to 'Always Allow' and 'Allow' in the keychain app (at least mine). Using Mac OS 10.6.8 and Thunderbird 17.0.4.

This review is for a previous version of the add-on (1.1.5.1-signed.1-signed). 

That shouldn't be happening, obviously (and I just tested that version of Thunderbird—it works ok for me)

Two things to try:
1) Make sure your OS X thinks your Thunderbird binary is correctly signed.
From a Terminal, run (adjust the path to the app as necessary):
codesign -vvvv /Applications/Thunderbird.app
You should see:
Thunderbird.app: valid on disk
Thunderbird.app: satisfies its Designated Requirement
If not, delete Thunderbird and reinstall.

2) Enable debug logging:
- Go to Preferences, Advanced, General Tab, and click on the Config Editor button
- search for signon.debug - double click to set it to true
- restart
You should now see more detailed logging either in the Error Console. If that doesn't obviously identify the problem for you, please feel free to report a bug: http://code.google.com/p/mozilla-keychain/