> Why does the ip address i set (192.168.1.101) get lost?

The flow is a bit different. It works like this:

a) you set the IP address of the FB server;

b) Jaybird connects to the specified address on the specified port and
tells server that it wants to subscribe for events;

c) FB server opens new server socket on some IP address and some port
(see firebird.conf parameters) and replies to Jaybird with this information;

d) Jaybird starts a listener thread and connects to the IP address and
port that was received from server and tries to read data from the
socket with blocking read (need to check, otherwise there is periodic
reading), and waits for data from the server;

e) When some even occurs, FB server sends some data into that newly
opened socket, Jaybird receives them, interprets, reports to the client
and wait for another portion.

In your case Jaybird was able to connect to server (step b), IP address
192.168.1.101), but receives 0.0.0.0 from FB server at step c) and
produces an exception at step d).

Therefore, please check the FB server configuration.

As to the exception, you should access the second exception in a chain -
first one is primary error code (335544721) and is of type isc_arg_gds,
not isc_arg_interpreted. Fix your code to:

GDSException gdse = (GDSException)fbe.getInternalException();
System.out.println("GDSE message: "+gdse.getNext().getParam());

Roman