Spell check for Firefox is not working after 2.5.8 update. I checked to see if Chrome was working and it was. I checked if Correct spelling as you type was turned on for FireFox and it was. Also, I have Pspell installed in the same area as your parameters usr/bin/aspell and JCE comes back and says it isn't there.
It seems that module parameters haven't been configured properly. Please make sure that you are using a valid twitter username, and
that you have inserted the correct keys. Detailed instructions are written in the module settings page.