Error during RT::Extension::Announce initdb

Hi all,
I was installing RT::Extension::Announce just now. Running
perl Makefile.PL
told me to run
make initdb
for first-time installations, so I did. In the course of that, I got the
following error:
[23258] [Thu Dec 8 17:39:31 2016] [error]: Invalid Custom Field values
source (/opt/rt4/sbin/…/lib/RT/Handle.pm:1145)
Done inserting data.
Done.

Is this anything I need to worry about for the extension to work properly,
or, in fact, do I need to worry about it for any reason? Thanks.

Alex Hall
Automatic Distributors, IT department
ahall@autodist.com