Bug#3226: pkg update-alternatives confusion

[Bill Mitchell <mitchell@mdd.comm.mot.com>]

Package: dpkg
Version 1.2.0

A coworker has been installing debian from recently downloaded
files.  He's been using dselect, no direct use of dpkg.  He
had installed nvi, vim, and elvis; and wanted elvis as his
default editor.  He hadn't figured out how to accomplish that
but, in the process of trying, had manually rearranged some
links in /etc/alternatives.

I used dpkg --remove to get rid of nvi, then did the same thing
with vim.  However, we were left with /usr/alternatives/vi pointing
to /usr/bin/vim, which did not exist.

I manually re-pointed it to /usr/bin/elvisnox, and that allowed
him to use vi.  However, subsequent attenpts force the links to
consistency with "dpkg --install elvisx11.deb" produce a message
to the effect that updates to /etc/alternatives/vi are "disabled".

I haven't had time to look at the update-alternatives script
to figure out why it wants to "disable" updates and, not being a
perl programmer, I'm really not anxious to do that anyhow.

Question:  How does my co-worker convince update-alternatives
to update /etc/alternatives/vi when vi packages are changed?

Bug:  I guess that I'm concerned that it was so easy for him to
get into this mess, and that it's not clear how to get out.