This has been broken (did not track consecutive failed login attempts from
the same client IP address) since the IPv6 commit of Aug-2015. I only noticed
this wasn't working when I was documenting the "auto-block hackers" feature
on the Wiki and noticed that every failed login (even those from the same IP)
was listed as a separate entry in the "Failed Logins" list (e.g.
sbbsctrl->View->Login Attempts). Ugh.