This is entirely user land and requires no kernel patches. The program then sets up a host route to this ip address via ifirlan, adds a proxy arp to ifeth for it and generates a gratuatous arp on ifeth.
Second part is executed as gratarp ifirlan.
I have some static routes which are host 10.192.0.1 dev irlan, and net default gw 10.192.0.1 dev irlan. Please use latest DHCP software.