[plug] Changing NIC address permanently

[J Michael Gilks]

Haven't been around for a while, but I need a bit of help with changing the 
address of a NIC on a firewall.
The system is an IPCOP firewall and I want to change the blue interface face 
192.168.2.254 to 192.168.3.254 permanently.
Can change it using ifconfig eth1 192.168.3.254 but then I must repeat for 
every reboot.
Anyone please help.
Thank you.

Love
Mike.

ps I think that now I am supposed to use the ip command but I could not make 
sense of the man page.