Actually, the problem is not related to Gnome in particular, so this
instruction isn't valid. The "problem" is that the system will allocate
ports above 1024 to anonymous sockets (sockets that aren't bound to a
particular port). Whenever socket is created, it is assigned a (basically
random) port unless a specific port number is bound to the socket either on
creation or by the bind system call. So port 3050 could be in use by
something. Use fuser -n tcp 3050 to find out what (if anything) is using
3050. You will have to kill that process.

It would be preferable if interbase or firebird would request a port number
assignment from IANA, which could be assigned below 1024, which would
preclude such collisions. Of course, then the server will need to be suid,
and able to setuid/setgid itself to the correct non-root user after getting
its sockets setup.

--Dean

2. Prepare the installation:

Log in as root.
Use a plain text console to do this and be
sure
that all Gnome desktops are closed.
(One user reported that the Gnome desktop
(apparently ICEwm)
blocked port 3050. I could not reproduce this
here, but it seems that it uses port numbers
that aren't assigned in /etc/services for own
purposes)