I am currently evaluating Firebird for my company.
One of the requirements they have is to keep a log of login
attempts for auditing purposes.

Is this somehow possible with Firebird?
I found and tried Ivan Prenosil's suggestions at
http://www.volny.cz/iprenosil/interbase/ip_ib_isc4.htm
but all that ensued was a security database that didn't let
me login any more. It seems that replacing the USERS table with a
view with the same columns breaks the security system.

Can you give me any pointers?

Your,
Laurenz Albe