Changing line 81 of the postinst script fixes it:
$ diff postinst.old postinst 81c81 < --service-port=$port --service-user=zope $ZEOSERVER --- > --service-port=$port --service-user=zope:zope $ZEOSERVER
Changing line 81 of the postinst script fixes it:
$ diff postinst.old postinst port=$port --service-user=zope $ZEOSERVER port=$port --service- user=zope: zope $ZEOSERVER
81c81
< --service-
---
> --service-