Can someone tell me what's causing this log message please?

[Jim Reid]

>>>>> "Merlin" == Merlin  <robert at chalmers.com.au> writes:

    Merlin> named[118]: client 210.49.48.16#63012: update  'malcolmchalmers.com/IN' denied

I would have thought this message was self-evident. Your server
refused a dynamic DNS update for malcolmchalmers.com from port 63012
of 210.49.48.16.