Can anyone suggest a good way to make it possible for root to have a
small profile loaded automatically on su?  Essentially, I want something
like .cshrc, but for ksh.  ENV doesn't work, because the su'd sh is visibly
privileged.

The reason I want this is that my normal shell sets PS1, and exports it for
subshells, but I don't want to have the same prompt as su that I do as a
mortal; I consider it Bad Mojo.

-s