The root user was NOT enabled when I checked, but the person who I upgraded it for told me that the root user was enabled by a service person long ago, then disabled again, when it was running Jaguar.
I suspect this happened because of the other "ghost" account than suddenly appeared after I...
I just upgraded an iBook from OSX.2 Jaguar to OSX.4 Tiger.
The new log on screen shows a User account (named "Other") long ago deleted from the computer under Jaguar, including the disk image from the Users folder.
It does not show up in the Accounts System Preferences, nor in NetInfo...