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CloseReview for Folderpane Tools by RTaxi
Rated 4 out of 5 stars
It's right this add on wasn't updated, i found the solution at this page
http://kb.mozillazine.org/Thunderbird_3.0_-_New_Features_and_Changes.
You can find a link at this web page to the updated version of the add on, it worked for me !!
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