This has been bouncing around since 2005. The Washington Post did a story two years ago about how it was bogus - http://www.washingtonpost.com/blogs/fact-checker/post/did-ah...
So they got six years of mileage out of this lie, I guess it was time to kill it after six years, right? Not really. Let me see if any news outlet has drudged it up this month. Yes, Businessweek/AP did...
http://www.businessweek.com/ap/2013-10-11/new-iran-governmen...
'When the conference was first held in 2005, Ahmadinejad made his infamous remark that Israel should be "wiped off the map."'
So here it is eight years later and the major news outlets are still printing this lie as factual news. Even after it was authoritatively debunked by the Washington Post two years ago.