Rated 5 out of 5 stars

Thunderbird 7 will disable the plugin if you are using version 1.0.0, if you download version 1.0.2 from the author's support page and manually install, it still works as advertised!

This review is for a previous version of the add-on (1.0.0). 

I have uploaded a new version. If you can't wait download it from my website.