From FOXNews.com - Iran Shuts Down Gmail, Announces National E-Mail Service: "Iran's telecommunications agency announced Wednesday that it has permanently suspended Google's e-mail services and that a national e-mail service for Iranians will be rolled out soon"
In other words, this Islamic Extremist "government" that defies the will of its people in elections, is now doing everything possible to make sure that they control any information into or out of the country.
For those that don't understand the infrastructure of the Internet, this type of blocking is possible. The only "possible" (and by possible I mean chances are slim) way of getting around this would be bi-directional satellite- maybe. Perhaps there is another method but most would probably be controlled by Iran's telecommunications agency.
Next, expect reports to filter out of Iran about people being "lined up against a wall" and "the family being billed for the cost of the bullet."