cron weekly error message

1) release of Ubuntu
lsb_release -rd
Description: Ubuntu 12.10
Release: 12.10

2) version of the package
apt-cache policy dhelp
dhelp:
  Installed: 0.6.20ubuntu1
  Candidate: 0.6.20ubuntu1
  Version table:
 *** 0.6.20ubuntu1 0
        500 http://archive.ubuntu.com/ubuntu/ quantal/universe amd64 Packages
        100 /var/lib/dpkg/status

3) What you expected to happen
cron weekly runs without an error

4) What happened instead
dhelp cron weekly reports:

Error converting file: /usr/share/doc/libstdc++6-4.7-doc/libstdc++/html/_form0.ps

This file is part of the package libstdc++6-4.7-doc