[Plugin: NextScripts: Social Networks Auto-Poster] Double/triple posting on facebook

Hi,
I don’t know why, but the posts of my blog are shared more than one time (two or three times) on my facebook page. On twitter this never happens thanks to the “status is a duplicate” thing, but in the log I can see the second/third request of sharing on twitter too. Any suggestions?
Thanks,
Fabio.

http://wordpress.org/extend/plugins/social-networks-auto-poster-facebook-twitter-g/