Do a ipconfig /release and a ipconfig /renew on my windows client forces to get a new ip address. The DHCP log (see below) reflects that everything works ok, but no DHCP leases are shown in the GUI (see GUI.png).
Siggi
DHCPLOG ... STARTS
...
2011:04:26-12:45:50 sr-at-home dhcpd: DHCPRELEASE of 192.168.168.249 from 00:24[:D]2:f0:e2:36 via eth0 (not found)
2011:04:26-12:46:00 sr-at-home dhcpd: DHCPDISCOVER from 00:24[:D]2:f0:e2:36 via eth0
2011:04:26-12:46:00 sr-at-home dhcpd: DHCPOFFER on 192.168.168.249 to 00:24[:D]2:f0:e2:36 via eth0
2011:04:26-12:46:00 sr-at-home dhcpd: Dynamic and static leases present for 192.168.168.249.
2011:04:26-12:46:00 sr-at-home dhcpd: Remove host declaration REF_DhcMac0024d2f0e2 or remove 192.168.168.249
2011:04:26-12:46:00 sr-at-home dhcpd: from the dynamic address pool for 192.168.168.0/24
2011:04:26-12:46:00 sr-at-home dhcpd: DHCPREQUEST for 192.168.168.249 (192.168.168.1) from 00:24[:D]2:f0:e2:36 via eth0
2011:04:26-12:46:00 sr-at-home dhcpd: DHCPACK on 192.168.168.249 to 00:24[:D]2:f0:e2:36 via eth0
...
DHCPLOG ... ENDS