Compatible with Thunderbird 7.01? Rated 1 out of 5 stars

On the "Write" window, "Latex it!" has not been added to my toolbar.
I use Thunderbird_7.01 + WindowsXP_64

Notes:
- On cygwin, [utf8x] is not recognized either.
- I have installed everything as requested on 32bits versions (ghostscript+imagemagic).