Description of Problem:

The dhcpd.conf.sample as shipped in dhcp-3.0pl1-2 does not contain the required
parameter 'ddns-update-style ad-hoc;' which enables the depreciated (and broken
if you read the man page) DNS update functionality. Without this line dhcpd will
fail to run. Fortunately the error message is 'in your face' if not terribly
descriptive, and points to the man page. I would recommend adding the following
lines to the top of the /usr/share/doc/dhcp-3.0pl1-2/dhcpd.conf.sample file to
enable the 'interim' method of dynamic dns updates, but disable client updates
at the same time. (Less surprise that way) This way the dhcpd server can run,
and clients can't magically alter the DNS records.

ddns-update-style interim; # 'ddns-update-style ad-hoc;' is depreciated/broken
ignore client-updates;     # 'allow client-updates;' is default