Rated 5 out of 5 stars

Snakiej, and anybody who's got compatibility problem, here is a little trick:
Open 'application.ini' in the thunderbird folder, and replace 'Version=3.0' to 'Version=3.0a1'
save it, restart thunderbird and that's all
This trick is working with all addons.

This addon is perfect, my favorite feature is, that I can set to see the another email addresses of my contats, not only the default, without opening the contats window.

Unfortunatelly it doesn't work with portable versions of thunderbird.