I'm the guy who posted this. The provided answer didn't work on Ubuntu or Windows (it seemed to go into an infinite loop). I then tried SuperOneClick, and it didn't work either--then I noticed that ADB wasn't even detecting my phone. I tried installing the drivers from here, but that didn't help. Am I doing something wrong?
OP here. I used the info here to fix another (relevant, if I remember correctly) problem I had, then reinstalled the drivers, rebooted, set the phone to "Camera (PTP)" mode, and let Windows do it's "installing drivers" thing. It works now.