i am using rh 6.1 and have upgraded to latest v of bind and dhcpd to test with cisco automatic dhcp/dns server, it appears that the curent dhcpd does not transmit the node name in the ip header to automaticly update the dhcp/dns server, (works fine w nt4 & win2k), it would be nice if someone would look at this, it can be validated by using a sniffer to look at the ip header which is blank in the node name field
dhcpd will be updated in a future release to the ISC one that supports DDNS...