Well, that's embarrassing. :)
The issue is coming from client/facileManager/fmDNS/www/reload.php. Fix will be rolled out in fmDNS-1.0-rc4-3, but if you are impatient and don't want to build configs as a workaround, you can run the following on your clients:
perl -npi -e "s/$domain_id/$_POST['domain_id']/" /usr/local/facileManager/fmDNS/www/reload.php
This is a result of breaking up some code to support future modules.