Authentication Error when trying to bind client to Open Directory

I know the diradmin password, and I've even tried resetting the password just in case and still no luck in getting the client to bind to the server. It keeps telling me authentication error - invalid username or password. I'm 100% sure the admin username is diradmin (default) and I'm 100% sure on the password. Caps Lock is not on, I've tried everthing. At this point I'm thinking I found a bug. Any ideas?