"Head...Shoulders...Knees and...SOCKS!"

So I was at the Gap this morning and heard Aimee Mann's "That's just what you are" over their sound system, which reminded me again how awesome that song is. The next song was "Our lips are sealed" and it also sounded pretty good. It has just occured to me that this could have been that new cover version by the Duff sisters, but I hope not - because I enjoyed it. Did Aimee Mann ever do a cover of this song? And if so, where can I find it?