Supposedly, Iranian Minister of Communications and Information Technology, Major General Mohammad Hassan Nami promised last week to reveal a picture of the messianic Mahdi on the eve of the Iranian elections.
Since then, Arab media has been showing this photo of a veiled person, claiming that it came from an Iranian news agency and is indeed the supposed Mahdi.
I can't find any evidence that these images were in fact in the Iranian media, so almost certainly this is another attempt by Sunnis to make Shiites look like fools. In fact, according to the news accounts, this Mahdi is "not be a Muslim but will be of the religion and the law of the Jews, and the law of the Jews will judge the world according to their messages.
Arab news media does things like this all the time, yet Western media still believes what they have to say when their fanciful stories happen to fit the conventional wisdom - and they simply ignore the obviously crazy stuff.