>> Would it be possible widen for new edition of Firebird the length of
>> authenticity of the key of the user for not being in the need of
>> searching another RDBMS and keep using this one as I've used until now?
>
> unlikely to happen any time fast.
> You should probably look at using trusted authentication, then you can use
> the server authentication.

Alternatively you can hash application user password to 8-bytes
length before sending it to server. It would even improve security
because users hadn't been able to use third-party tools to connect to
database.

SY, SD.