This question already has an answer here:
I've looked and looked for an answer - but I like Ubuntu's login manager, and can't figure out how to change lubuntu's to it.
I've installed Unity using these instructions: How do I install LXDE / Lubuntu?, but can't do that with the login window! Help, I'm a newbie!
P.S. I have Lubuntu installed on a USB key - hence, I don't want Ubuntu as the main install, but just for tinkering from time to time.