Feisty (7.04) Installer does not allow user 'hal'

Fresh install of Feisty-desktop-386 from CD to primary (hda) hard drive. Existing Dapper (6.06) install on hdb used as source for migration of settings. In both the migration account and establishment of user account/password, user 'hal' was not allowed. I used 'halb', and that was accepted. After installation and initial configuration, I changed all instances of 'halb' to 'hal' inj /etc/shadow, /etc/passed, /etc/group, changed /home/halb to /home/hal, and all instances of 'halb' to 'hal' in /etc/hal/.gnome2/sessions, deleted and changed password for user 'hal' with "passwd -d hal" then "passwd hal" while in single-user mode. This was after checking that the name 'haldaemon' was still in effect as a result of the same problem in Dapper testing.

Note: I have been 'hal' long before Deb and Ian met ;-)

Hal