It might be the same problem as this one:

===================
>> ! Font \T1/cmr/m/n/10=ecrm1000 at 10pt not loadable: metric data
>> not found or bad.
===================

It looks as it is the same problem. I have run tftopl + pltotf on the fonts, but it does not work.
I get the problem even with cmr:

===================
C:\Archivos de programa\TeXLive\texmf\tex\eplainJA>luatex -ini minimum_font.tex
This is LuaTeX, Version snapshot-0.25.4-2008071819 (Web2C 7.5.7) (INITEX)
(minimum_font.tex
! Font \tenrm=cmr10 not loadable: metric data not found or bad.
===================

> There is a luatex fix in svn

I have not yet tried. I'll first have to learn to work with svn. Hope next week
I'll have some time.

Chao
Javier A.