Change name in Comments from User Login

I've installed Acrobat 9 Pro. It has picked up my user name (Kathy) from my computer. But I'm commenting on files that are being commented on by other people named Kathy. I need to change the name in my comments.

I've seen the video in the tutorial here: http://www.acrobatusers.com/tutorials/change-comment-identity-acrobat

In the tutorial, Bowman is working in Acrobat Pro Extended. This fix does not work in Acrobat Pro. Yes, you can change the name in an individual comment, but checking the "Make properties default" box does not mean that the changed user name will show up on your next comment. (Properties like color become the default; the user name does not.)

Does anyone know a way to change this so I don't have to modify the name on every single comment? (And why, oh why, does Adobe insist on picking up your computer's user name and putting it in the Preferences > Identity box all grayed-out so you can't modify it [i]there[/i]--where it would make the most sense?)

Signed,

Kathy, who can't type her last name without an error...