If you are not able to make the keyconfig extension work with your current version of Thunderbird (2.0, 3.0, 3.1, ¿4.0?), and gets marked as ‘not compatible’ with this version of Thunderbird, it’s just not true, but you need to tell it so.
Now, exit Thunderbird!
The way to do that is going to your profile directory (mine is on linux, on the /home/myusername/.mozilla-thunderbird/profile_id.default/
and over there, edit the extensions.rdf file, search for the text:
And some lines below that, look for:
Delete that line, and leave it as follows:
Now, in case you installed functions for keyconfig, do the same searching for:
name="functions for keyconfig (Thunderbird)"
Now you need to edit this two files:
where you just need to bump up the lines, changing the 3… with 3.*:
Now, start Thunderbird, and it should work for you!
Besides, for the adventurous you can check some functions to add to Keyconfig