Interestingly enough, the one Iranian I had gotten to know in the last few years said he was Zoroastrian.
In case anyone else wanted to know what the religious breakdown is in Iran, Wiki's Iran page gives the following:
Religion in Iran is dominated by the Twelver Shi'a branch of Islam, which is the official state religion and to which about 89% of Iranians belong. About 9% of Iranians belong to the Sunni branch of Islam, mainly Kurds and Iran's Balochi Sunni. The remaining 2% are non-Muslim religious minorities, including Bahá'ís, Mandeans, Hindus, Yezidis, Yarsanis, Zoroastrians, Jews, and Christians.