I have ZoneDirector 22.214.171.124 build 232. It is configured with TACACS+. TACACS+ server is shrubbery.net tac_plus, with AD backend through PAM on RedHat Linux. I would say that is fairly common setup. TACACS+ is working completely fine in all Cisco devices for all users.
But on ZoneDirector all users who have a space character in their password cannot login. I have tested this and it is a bug in ZoneDirector - space character in password prevents login.
Password like this works (user can login through TACACS+): P@ssw0rd Password like this and the user cannot login: P@s w0rd
The only difference is the space character in the middle of the password.
It is very annoying since we have a long-standing company password policy that encourages the usage of long passphrases and not those difficult and not-so-secure "complex passwords".