RT 3.6.1 install | can't log on

RT 3.6.1 on RHEL 4.0

No problems whatever building RT for a change! Everything seems to
be working fine but when I try to log in to RT as root/password, I
get : Your username or password is incorrect

I don’t think I did anything that would have disturbed the default
RT root password, but what can I do to check/fix this?