Folk, there is simple trick to reject SYSDBA access just now - just
create ROLE SYSDBA. Neverthelles, don't you think that opened source
moved IB/FB forever out of the class of RDBMS for systems with high
requirements for security? It's not a very big problem to build server
that ignores any rights at all. BTW, some developers of light-weight
local systems wants to have such a build to increase performance.

Best regards.