SMS or mobile text messaging is playing a big role in Tehran these days. You can't have a mobile phone and not receive several text messages everyday. Jokes, short news, rumours, etc. they are now officially part of campaigns.
But today, "according to ISNA":http://www.isna.ir/Main/NewsView.aspx?ID=News-544160 , Saeed Mortazavi, chief prosecutor of Tehran, has released a warning for people who use SMS to spread news, views, and jokes for or against candidates, usually against the fundamentalist candidate, "Mahmoud Ahmadi Nejad":
Those who don't comply "will be prosecuted and their phones will be seized," the note reads.