dv_version? what is that about?

["Jacob Schmude <Your Jacob Schmude" <jacobs@ncinter.net>]

Hello

When trying to upgrade to the latest potato release I get the following error:
db_version: command not found
dpkg: subprocess exited with status error 127

There's no package that seems to be associated with the error and there's no db_version command on my debian system.

The commands I entered as root were:
pon (start ppp connection)
apt-get update (update package list)
apt-get dist-upgrade (upgrade the packages)

It downloads fine and install some packages but fails with that error.