About RSS system

I have installed the XenPorta addon and get RSS from a forum that I make into news forum on my Facebook. But anytime I edit my news thread or there anyone comment my thread, it update again on my Facebook. Is there any way that prevent this, make one news appear on Facebook on ly one time?
No, that is not a problem of add-on, XenPorta just use a forum as News source. And the RSS I got is in 'real' forum, not from xenPorta. Sorry about my English but I hope you understand :(
Then if there is an edit or comment, it will keep appearing like that? I dont want the news appear in my FB many times, seem that I must delete this RSS on my FB :(