nstaller and Accounts not accepting password

I am encountering the error "Please try again." after entering a name and password when attempting to install software or unlock the Accounts preference. Everything was working fine until today. My password still works during startup, but my screensaver does not accept the password either.

Yesterday I created a user using dscl in the terminal. I am assuming my troubles are related to that. Any recommendations?

MacBook Pro
OS X - 10.5.8

UPDATE:

Turns out I made a dumb mistake (of course...that's usually what it comes down to). When I created the new user using dscl, I inadvertently used the same user id.

For some reason, I could log in okay with my original Admin username/password, but after a random period of time (at least I could not identify a pattern), the second user would magically take over.