So far this has only been reported by Fox News, who have an obvious axe to grind, but I'd be interested to see if any person or news organization disputes the facts, recounted (plus a copy of the actual letter) on The Smoking Gun:

Comedian Al Franken last month wrote an apology letter to Attorney General John Ashcroft, admitting that he was not truthful when he previously sought Ashcroft's views on abstinence.

...

Franken's missive, written on letterhead from Harvard University's John F. Kennedy School of Government, claimed that he had already received abstinence stories from other prominent Republicans, including Condoleezza Rice and Senator Rick Santorum. However, in his July 11 apology, Franken admitted that he had not received those abstinence stories and called his solicitation to Ashcroft, "an imprudent attempt at satire."

Well, it's handy only being a "comedian" or "entertainer" (a somewhat cowardly categorization that other media personalities, like Rush Limbaugh, like to hide behind).

See, he was making a joke, by using letterhead from a school he was no longer associated with and claiming that he already had personal accounts from Ari Fleischer, Condoleeza Rice, and Rick Santorum.

It's convenient to always be able to pass off a slip of the tongue or a misrepresenting letter as a joke.

I wonder, which is more of a lie: Mistating the type of media award you won, or sending a letter to a high-ranking government official with false information and on false pretenses?