What's a Little Perjury Between Friends?

Atrios and Roger Ailes (the good one, not the Fox one) each point out this passage from today's Wall Street Journal editorial page about Patrick Fitzgerald, special prosecutor in the Valerie Plame leak case:

It may be that he too has concluded that talking to the press is no crime, in which case he may by now only be pursuing a perjury rap against the leaker. If that's true, Mr. Fitzgerald will have earned a place in the Overzealous Hall of Fame.

Maybe my memory is going, but didn't purjury used to be considered an impeachable offense?