Internet access cut off in Iran

Israel Radio reports (11:00 pm) that internet access in Iran has been cut off for the last 72 hours in what is believed to be an effort to prevent the Iranian opposition from rallying its supporters. At least that's why Israel Radio says it's happening. They're saying that you can't send emails from Iran right now, so if you're in Iran and reading this, please feel free to drop me a note.But why