begin kludge
interface fddi0/0
ip address yor.own.net.work your.mask.as.desired
ip address bill.assigned.c.net 255.255.255.0 secondary
end kludge;
If the box decides to send a ICMP message out on the interface
that faces the RA pirated network it will use the primary address, so
it will show up with the name and network number you prefer.
-Peter