DHCP address problem after etch upgrade

[David Jarvie <lists@astrojar.org.uk>]

After my latest upgrade this week (I'm running etch), the DHCP address 
allocated to my machine has changed from being one allocated by my DHCP 
router to being some external address. This results in the machine on my 
network not being able to see my machine.

Previously, the router allocated an address with a subnet mask 192.168.0.255. 
Now ifconfig is showing 169.254.106.31, which means that the other machine, 
which has address 192.168.0.101 can't see me. What is strange is that I'm 
getting the normal DHCP setup messages on the console:

DHCPREQUEST on eth0 to 255.255.255.255 port 67
DHCPREQUEST on eth0 to 255.255.255.255 port 67
DHCPREQUEST on eth0 to 255.255.255.255 port 67
DHCPACK from 192.168.0.1
bound to 192.168.0.100 -- renewal in 302400 seconds.

but the actual address is different. I tried disconnecting the router from the 
outside world, and the address then was 192.168.0.100 (which is what I used 
to get, and what I want). I presume that when I'm connected, the DHCP request 
is getting transmitted to my ISP and its reply is being picked up and is 
overwriting the 192.168.0.100 allocated by the router.

Is it possible to make dhclient filter out any address which is not 
192.168.0.x so that my network works?

-- 
David Jarvie.