AD login name changed – how to fix on the local Mac to allow login to old home folder?

I'm using AD for credentials, and OD for MCX. I have a user that was just married, and now has a different last name. Our username format is lastnamefirstinitial - i.e. jonesm for Matt Jones. Though the user's name has changed, she still needs to be able to login to her 'old' account. When she tries her new username and password, she can't login. When she tries her old username and password she can't login. I can still see her home folder, and I used the info on the KB to login as root and change her home folder name, in the hopes that when logging in it would see that there's already a homefolder present. Instead the login panel just shakes. I have 2 questions - 1) is there a standard way to go about updating the Mac side of things to get back in step with an AD username change 2) Shouldn't her mac have just created a new home folder if it didn't recognize 'new' username?