[luatex] problem with a .pk file

[Élie Roux]

Hello,

this plain TeX minimal example shows different output when compiled
with pdfTeX and LuaTeX (0.50):

\font\toto=frca10 at 10pt\toto
ligature
\bye

the frca10 comes from the package frcursive
(http://www.ctan.org/tex-archive/fonts/frcursive/), present in TeX
Live 2009. The pdf contains ligat when compiled with LuaTeX and
ligature when compiled with pdfTeX. Is it a problem in the .tfm/.pk
file or is it a bug in LuaTeX?

Thank you!
-- 
Elie