Solved.
Thanks all, it was a port forwarding issue on the server side.
Opening another thread with my real problem, the one I was trying to replicate.

--- In firebird-support@yahoogroups.com, "cruvadom" <cruvadom@...> wrote:
>
> Hello,
> I established a superserver firebird 2.5 server on my computer (win xp Sp2) and am trying to connect it via tcp/ip from another computer (win 7), using latest ibexpert version.
>
> Error message:
> ----------------------------------------
> Unsuccessful execution caused by a system error that precludes successful execution of subsequent statements.
> Unable to complete network request to host "79.177.37.20".
> Failed to establish a connection.
>
> [005453DA]
> [00541619]
> [00518957]
> [005418A4]
> [00FA0512]
> [00F40FB8]
> [00EC411B]
> [004257B3]
> [004E5D00]
>
>
> no firewall on the server side (which is on my computer).
> simple ping works.
> Any ideas? must be a simple thing that I miss.
>
> Thanks,
> Gil.
>