shorewall fails to uninstall

After installing shorewall and *not starting* it, it fails to uninstall:

root@TUPHZIT-JOWI:~# aptitude purge shorewall
The following packages will be REMOVED:
  shorewall{ap}
0 packages upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
Need to get 0 B of archives. After unpacking 1,826 kB will be freed.
Do you want to continue? [Y/n/?] y
(Reading database ... 226183 files and directories currently installed.)
Removing shorewall ...
Stopping "Shorewall firewall": not done (check /var/log/shorewall-init.log).
invoke-rc.d: initscript shorewall, action "stop" failed.
dpkg: error processing shorewall (--purge):
 subprocess installed pre-removal script returned error exit status 1
No apport report written because MaxReports has already been reached
                                                                    Errors were encountered while processing:
 shorewall
E: Sub-process /usr/bin/dpkg returned an error code (1)
A package failed to install. Trying to recover:

root@TUPHZIT-JOWI:~# cat /var/log/shorewall-init.log
   ERROR: Shorewall has never been started
   ERROR: Shorewall has never been started
   ERROR: Shorewall has never been started
   ERROR: Shorewall has never been started
   ERROR: Shorewall has never been started
   ERROR: Shorewall has never been started
   ERROR: Shorewall has never been started

It seems one has to configure and start shorewall before it is possible to remove it again.

Is there another way to force a purge/remove?

dpkg -r --force-all shorewall
does not work.

Cheers,

Johannes

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: shorewall 4.4.26.1-1
ProcVersionSignature: Ubuntu 3.2.0-41.66-generic 3.2.42
Uname: Linux 3.2.0-41-generic x86_64
ApportVersion: 2.0.1-0ubuntu17.2
Architecture: amd64
Date: Wed May 15 10:33:29 2013
InstallationMedia: Ubuntu-Server 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120817.3)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=screen
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: shorewall
UpgradeStatus: No upgrade log present (probably fresh install)
mtime.conffile..etc.default.shorewall: 2013-05-15T08:49:53.979684