Yes, although I'm not 100% sure how.
I got in the car, turned it on, put it in reverse, the doors locked automatically when I put it in gear, I saw the paper under the wiper, put it in park, got out to take it off, and the door was locked.
I swear I have no idea how it locked behind me when I got out.
Supposedly the doors on the '04 Ion didn't auto-lock until you hit 25mph, but there I was, in the parking lot.