dchpd errors - are these to do with DNS?

[Henry Law]

[I'm running Smoothwall in fact; tried the Smoothwall group but got no
answer so I'm down to debugging the components myself...]

For those who don't know, Smoothwall runs dhcpd on the local network,
and dnsmasq to provide DNS forwarding from the ISP.  I recently
changed the address range of my local network to 174.24.0.192/26 and
since then I'm getting continual entries in the logs of this form:

"11:04:42 dhcpd DHCPOFFER on 172.24.0.240 to 00:00:21:26:1a:7e
(main-atx) via eth0

"11:04:42 dhcpd if IN A main-atx. rrset doesn't exist add 1800 IN A
main-atx. 172.24.0.240: timed out.

"11:10:50 dhcpd DHCPINFORM from 172.24.0.240 via eth0: not
authoritative for subnet 172.24.0.192

(Apologies for folding: those are three successive lines).  Research
suggests that, rather than being anything to do with DHCP these are
actually dns or ddns messages, associated with dnsmasq, but I don't
have ddns running.   And despite these messages DHCP and DNS continue
to work flawlessly!

Can someone confirm or refute the hypothesis that these are
dns-related messages, and if so point me in the right direction to
resolve the problem?

[Apologies if this is a duplicate; the original is not on my news
server and I've checked Google groups to confirm that it's not there
either]

Henry Law       <><     Manchester, England 
.