on upgrade lucid -> precise /etc/default/isc-dhcp-server is not migrated

When upgrading from lucid->precise the /etc/dhcp3/dhcpd.conf file is correctly migrated to /etc/dhcp/dhcpd.conf, but the settings in /etc/default/dhcp3-server are not migrated to /etc/default/isc-dhcp-server. This leads to the service losing its interface specifications potentially allowing it to serve addresses on the wrong interfaces. Bad.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: isc-dhcp-server 4.1.ESV-R4-0ubuntu5
ProcVersionSignature: Ubuntu 3.2.0-24.38-generic 3.2.16
Uname: Linux 3.2.0-24-generic i686
ApportVersion: 2.0.1-0ubuntu7
Architecture: i386
Date: Thu May 24 15:29:35 2012
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: isc-dhcp
UpgradeStatus: Upgraded to precise on 2012-05-24 (0 days ago)
mtime.conffile..etc.dhcp.dhcpd.conf: 2012-05-24T09:04:21.549574

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[rational]
Config file isn't migrated, leading to duplicate configuration files and lost settings.

[test case]
1) Install dhcp3-server on Ubuntu 10.04
2) Edit /etc/default/dhcp3-server and change INTERFACES to point to eth0 (for example)
3) (ugly trick) manually update /etc/apt/sources.list to point to precise and include precise-proposed
4) sudo apt-get update
5) sudo apt-get install dhcp3-server (a full dist-upgrade won't work, but selective upgrade of just dhcp3-server will work)
6) Ensure that dhcpd is running, that /etc/default/isc-dhcp-server contains the change you did pre-upgrade and that /etc/default/dhcp3-server no longer exists

[regression potential]
If the previous configuration was broken, the new one will be broken too, but that's really what you'd expect from an upgrade...