"Official POSIX builds for Firebird v.1.5 and higher do not use 'masterkey' as the default password. Instead, a password is randomly created during the running of the installation scripts and written into a text file named SYSDBA.password. If 'masterkey' returns a 'user name and password not defined' error, it is likely you are using a build that conforms to the POSIX build rules in this respect."
Ha tényleg ez, akkor kb. 10 másodperc volt megtalálni, még mobilnettel is (google).