Hi!
I have FC5 with the default firewall. I would like to create a new rule which would allow a specific IP-address to do everything. The graphical Tool to configure the firewall allows only to specify ports or dämons (sshd usw...) but not to specify other things like Ip-Address. Is there a way to configure this default firewall or do I have to abandon it in order to create this one rule?
To make things maybe more clear: the problem for me is not to write this one rule (the syntax wouldn't be a problem), but to find the way how to include it in this default firewall, since I have to use its configuration's tool.

I'm not sure exactly how to add a specific rule to the default firewall. One easy way of doing this is to download firestarter (yum -y install firestarter). It's a GUI based iptables rule generator. It will allow you to do those kinds of things.

Thanks! I've just installed firestarter, very interesting so far! Unfortunatly it seems to start the iptable all over again, without re-using the rules that have been defined so far. Or is there a way to import rules that have been pre-defined?

Fedora uses service scripts. You can add a rule via the command line and then to save run the command:
services iptables save
or
iptables-save

Fedora uses service scripts.
The rules are saved in /etc/sysconfig/iptables. When the iptables service starts the rules are read. When the rules are save via the above commands they are rewritten to this file.