A colour code for Iran's 'infidels'

I've finally had a look at Amir Taheri's article in the National Post - A colour code for Iran's 'infidels' - and it doesn't mention Iranian exiles as his source for the article. He also quotes from various Iranian officials, and seems to have very detailed information. I am wondering what the truth is - is the Iranian government denying this story because it casts such a negative light on the country, or is it doing so simply because the story isn't true? An Israeli expert on Iran also denies the truth of this report. I hope we'll learn in the next few days what the truth is.