An Iranian clergyman performs the weekly noon prayer at Tehran university on the first Friday of the holy month of Ramadan, on September 5, 2008. Muslims across the world are observing the holy month of Ramadan, the ninth and holiest month of the Muslim calendar, which is traditionally determined by the sighting of a new crescent moon. Practicing Muslims desist from eating, drinking, smoking and any sexual activities from dawn to dusk during Ramadan.  AFP PHOTO/BEHROUZ MEHRI (Photo credit should read BEHROUZ MEHRI/AFP/Getty Images)