> But still there's something wrong (maybe not with IBObjects, I

can't

> say really...)
>

...

> c) When specifying the port number 3050
>
> DatabaseName := 'localhost/3050:c:\mydb.fdb';
>
> I get an ISC error message
>
> ISC ERROR:
> Unable to complete network request to host 'localhost'
> Failed to locate host machine.
> Undefined service 3050/tcp.
>

Hello, problem solved. That was because gds32.dll of InterBase was
used by mistake instead of Firebird's client lib(s).

As I found out, the port number can't be specified in the connection
string for an InterBase server, for IB just service names
(like 'gds_db') work.

Was not an issue of IBO, happy now :-)
A.B.