Possible Duplicate:

How to add user without useradd command?

I am trying to add users in Lubuntu 12.04. I have followed the instructions here which amounts to:

$ useradd username

$ passwd username

I entered the password twice, and everything seemed good. But when I try to use the username and password from the Lubuntu login screen, it fails, simply returning to the login screen.

(Note that this is not the 'incorrect password' behavior that my working account displays.)

Any ideas?