Why is IBEvents not catching the event?

Question

Delphi

From the program I successfully connect to the database with DBA rights. I call a stored procedure. The procedure successfully executes and sends the POST_EVENT 'refresh' message to the program;
In the IBEvents program, it is subscribed to the refresh event, the AutoRegister=true property, the IBEvents.OnEventAlert handler is configured. The event handler does not work at all, the breakpoint in the handler does not work.
What was done to identify the error: 1. Insert current_timestamp into test_table was inserted into the stored procedure. Procedure fulfills, in the test table there are new records.
2. Only the event dispatch code is left in the procedure in order to exclude the influence of the procedure code on the event dispatch.
3. Firewall disabled. I tried to connect to the database by IP, by IP localhost, locally with the full path to the database.
4. Instead of auto-registration of events, I did forced registration after connecting to the IBEvents.RegisterEvents database
5. Compiled with native IBX components in Embarcadero XE7 and the second variant with native IBX components in Delphi 7.
Why doesn't the event handler work?

Answer 1

Events are sent through a separate connection, apparently it was not allowed by the firewall / firewall.
In the config C:\Program Files\Firebird\Firebird_<FB version>\firebird.conf, remove the comment from the line:
#RemoteAuxPort = 0 and specify a fixed port number
and open this port for connection