Auditor confusion

using trunk r2301.

Signing this zone:

$ORIGIN sion.
$TTL 86400

@ IN SOA ns1.nic.uk. hostmaster.nominet.org.uk. (
1222334147 ; serial no
2H ; refresh
5M ; retry
4W ; expire
3H ) ; minimum TTL

IN NS ns1.nic.uk.
IN NS ns2.nic.uk.
IN NS ns3.nic.uk.
IN NS ns4.nic.uk.
IN NS ns5.nic.uk.
IN NS ns6.nic.uk.
IN NS ns7.nic.uk.
IN NS nsa.nic.uk.
IN NS nsb.nic.uk.
IN NS nsc.nic.uk.
IN NS nsd.nic.uk.

test IN A 1.2.3.4

gives the following auditor messages:

Oct 22 11:17:35 sion ods-auditor[23701]: Output zone does not contain non-DNSSEC RRSet : A, test.sion.^I86400^IIN^IA^I1.2.3.4
Oct 22 11:17:35 sion ods-auditor[23701]: non-DNSSEC RRSet A included in Output that was not present in Input : test.sion.^I86400^IIN^IA^I1.2.3.4

However if we change the $TTL statement to "$TTL 2D" I get:

Oct 22 11:21:10 sion ods-auditor[23955]: Output zone does not contain non-DNSSEC RRSet : A, test.sion.^I2^IIN^IA^I1.2.3.4
Oct 22 11:21:10 sion ods-auditor[23955]: non-DNSSEC RRSet A included in Output that was not present in Input : test.sion.^I172800^IIN^IA^I1.2.3.4

If we add a second A record for "test", or an A record for "test2" it works fine.