howto properly stop dhclient, after interface is down?

[Johannes Wiedersich <johannes@physik.blm.tu-muenchen.de>]

I temporary ran my wifi card and brought it down:

dhclient eth2
ifconfig eth2 down

- all from the command line.
Now, I realize that dhclient is still running

jw@johannes2:~$ ps aux |grep dh[c]
root     11352  0.0  0.1   2672   524 ?        Ss   18:17   0:00 
dhclient eth2

What is worse is that it apparently blocks my /etc/resolv.conf to be 
properly overwritten with the nameservers for my new wired connection.

I can't find a hint in the manpages of how to stop dhclient, short of 
killing it.

What am I missing?

How can I force resolvconv to rewrite my /etc/resolv.conf and use the 
settings from /etc/network/interfaces?

Running etch.

Thanks,
Johannes