That's it ! Back to the light.
Thanks !
Now something else:

I try do do the following:
If my app run's for the first time I set up the connection (with Connection
dialog from IBO_Login) and write a registry key with the full path of the
Database and the server name).
Next time, I read the Path and Server from the Registry, but the server
name appeares in front of Path (ex: 'linux:linux:/tmp/mydb.gdb' instead
of'linux:/tmp/mydb.gdb').
I need also to change the Database from my app.(Connect to another
Database).
The problem is that Server, Path and Protocol properties are not updated
after the connection is made.
Am I missing something ?