You wrote that you added the -R flag to udhcpc in April 2010, the version that comes with the new SHR unstable in October 2010 still has the commandline "/sbin/udhcpc -i eth0 -n" (no -R)
Is it possible to encode the wpa-psk with wpa_passphrase instead writing it as cleartext to ~/.config/iliwi/preferred_networks?
(a bigger one) Can you split iliwi into a small daemon and a user interface, where the latter could be unloaded and the connection remains established?