[luatex] accented characters in plain luatex

[Bob Tennent]

 >It is indeed in ISO-8859-1 (a.k.a. latin-1).  You need to tell your
 >editor, whatever it is, to save the file in UTF-8.  In this case I
 >suppose the original file was in latin-1, so you need to convert it if
 >you want to compile it using LuaTeX.

The editor is vim. Rather than figure out how to save in UTF-8, I used

iconv -t UTF-8 -o minimalUTF.tex minimal.tex

Now the accented characters don't display properly and although luatex
processes minimalUTF.tex, the accented characters are missing in the
resulting dvi.

As for luainputenc.sty, if I use it as follows

\input luainputenc.sty

I get \NeedsTeXFormat
                    {LaTeX2e}

despite the manual's 

  This package contains a .sty file for both LaTEX and Plain 

Bob T.