openjdk-6-jre removes icedtea6-plugin

[Sam_]

Install openjdk-6-jre which suggests icedtea-plugin and install openjdk-7-jre which suggests icedtea6-plugin.
Update alternatives, config and select openjdk-7-jre.
Purge openjdk-6-jre.
Result: it also removes icedtea6-plugin. No matter if using remove or purge, you won't have any icedtea-plugin left.
Expected:
Leave openjdk-7-jre suggestion alone, don't remove any suggestion from other packages.

~$ sudo update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection Path Priority Status
------------------------------------------------------------
  0 /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java 1061 auto mode
  1 /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java 1061 manual mode
* 2 /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java 1051 manual mode

~$ sudo apt-get -s purge openjdk-6-jre
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  icedtea-netx* icedtea-netx-common* icedtea-plugin* icedtea6-plugin* openjdk-6-jre*
0 upgraded, 0 newly installed, 5 to remove and 0 not upgraded.
Purg icedtea6-plugin [6b21.1.4-1ubuntu2]
Purg icedtea-plugin [1.1.4-1ubuntu2]
Purg icedtea-netx [1.1.4-1ubuntu2]
Purg icedtea-netx-common [1.1.4-1ubuntu2]
Purg openjdk-6-jre [6b24~pre3-0ubuntu1]

~$ sudo apt-get -s purge openjdk-7-jre
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  openjdk-7-jre*
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
Purg openjdk-7-jre [7~b147-2.0-1ubuntu2]

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: openjdk-6-jre 6b24~pre3-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-8.14-generic 3.2.0
Uname: Linux 3.2.0-8-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 1.90-0ubuntu1
Architecture: amd64
Date: Sun Jan 8 02:14:20 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20111129.1)
ProcEnviron:
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: openjdk-6
UpgradeStatus: No upgrade log present (probably fresh install)

[Sam_ (and-sam)]

openjdk-6-jre can be purged now since there is icedtea-7-plugin.