"Port Not Defined" problem

Alastair at Coriolis Systems sent me the following, he wanted to share:

Hi Jason,

We’re using your dkimproxy on Mac OS X. Anyway, we hit the "Port Not
problem, with Net::Server 0.91 (which is the one your package
specifies as a
minimum requirement).

I fixed this on our system by altering the dkimproxy.out code (we
aren’t using
dkimproxy on the inbound side as we have SpamAssassin). The change
was, on
the line

$self->{server}->{port} = $srcport;

to add square brackets (since it looks like Net::Server is expecting
an array,
rather than a single value). i.e.

$self->{server}->{port} = $srcport ];