using both cobbler and koan 1.60 i see this
[root@virt02 ~]# koan -s 192.168.11.1 -D
- looking for Cobbler at http://192.168.11.1/cobbler_api
Error: Could not find a matching system with MACs: or IPs:
[root@virt02 ~]# ifconfig eth0 eth0 Link encap:Ethernet HWaddr 00:16:3E:59:16:91 inet addr:192.168.11.4 Bcast:192.168.11.255 Mask:255.255.255.0
# cobbler system report virt02 system : virt02 mac address : 00:16:3E:59:16:91 ip address : 192.168.11.4
should also say that koan 1.4.3-1 seems to be fine