DNS updates fail

[titantoppler at gmail.com]

Hi list,

I've been trying to set up another S4 DC on my network.

My old set up was a single S4 DC (alpha 12) running DNS as well. I
subsequently hived off the DNS service to a dedicated box by copying the
zone files from the original S4 DC to the new box.

The setup was thus:
dc1.domain.local - 10.0.0.4
dns1.domain.local - 10.0.0.3

I successfully installed S4 (alpha 21) last night on another box
(dc2.domain.local). I joined it to the domain using the instructions from
here (https://wiki.samba.org/index.php/Samba4/HOWTO/Join_a_domain_as_a_DC)

On starting S4, however, I get an error message that says:
[2012/06/05 09:39:52,  0]
../lib/util/util_runcmd.c:334(samba_runcmd_io_handler)
  /usr/local/samba/sbin/samba_dnsupdate: update failed: NOTAUTH

I suspect it might be because I have not "authenticated" the new S4 install
(dc2.domain.local) - is this right? If so, how can I rectify that?

Cheers