vipw and vigr default editor

[John Ratliff]

When I run

sudo vipw or sudo vigr, it uses nano as the default editor. I've already 
used update-alternatives to select vim as my default editor, but this 
doesn't seem to work for vipw/vigr.

I have to do

sudo EDITOR=vim vipw

How can I make vim the default editor for vipw/vigr. Or how can I set 
the EDITOR variable when I use sudo automatically?

Thanks.

--John