> I knew there are some new API implemented in Firebird 1.5 RC7 like
> isc_get_client_version, isc_get_client_major_version(),
> isc_get_client_minor_version().
>
> However, I am not familiar with the header file of api written in
> delphi. The IBX shipped with Delphi doesn't has these new API.
> Could anyone point me where to download the latest header files for
> these API?

Firebird project does not have "official" Delphi header file, only C.
You can try to look at header files from components like
IBX, IBO, FIBPlus (but last time I checked them they were not
up to date(/with sync) with last Firebird 1.5),
or you can (like me) write your own header file
(with the advantage that you do not need to wait to someone else
to get latest version, and that you can write it exactly
to suit your needs).

Ivan