Adding user to dual boot laptop

[Gary Roach <gary719_list1@verizon.net>]

I have a Toshiba Qosmio with 2  60 GB hard drives, one with Windows XP 
and the other with Debian Squeeze. I just decided to add my wife as a 
user to the linux side. For some reason the login screen won't work. I 
set up her account in passwd and group and I set up her home directory. 
I can log her in as an su user with no problem. When I re-boot the 
system and the splash screen comes up (KDE4), I can enter her name and 
password but the system rejects the pass word. I've checked everything 
about 3 times and can find nothing wrong. I would guess that I have 
missed some niggally detail. The Windows XP side works fine. Any ideas?

Gary R.