\stemup \stemdown with grace notes!

[Paulo da Silva]

Hi,
SORRY, last time I forgot to attach the file!

In the attached file I can't get the
stem of the grace notes up while keeping
the other notes stem down (slur down, of course).
See treble measures 3 and 6.
Still buggy or am I doing something wrong?

TIA
Paulo da Silva
\header {
        composer = "Ludovic van Bethoven";
        title = "Sonatina em -Sol";
%       subtitle = "";
%       arranger = "";
        enteredby = "Paulo da Silva \& Ana Paula";
        copyright = "1999, Paulo da Silva \& Ana Paula";
        tagline = "(C) 2000, Paulo da Silva \& Ana Paula";
}
\version "1.3.37";

papersize = "a4"
\include "paper20.ly"
\include "portuguese.ly"

%{
      Entered by Paulo da Silva \& Ana Paula, 2000
%}


RH = \notes \sequential {
        \context Voice \relative  do'' \sequential {
                sol2(^" "^1^\textscript "Moderato (1/4=88)" "Large"_" "_\textscript 
"dolce" "italic" \grace {\slurdown si8(^3} \slurboth la8 sol la si |
                ) sol4 sol'8^5( \> )re^2 \stemdown \slurup re^4( )si^2 si^3( \! )sol 
\stemboth \slurboth |
                do2(^4_\p \grace {\stemup do8(^3} \stemdown si8 la si do \stemboth |
                )la4 re8(^3 mi re si^1 do^4 )la^2 |
                sol2( \grace {si8(} la8 sol la )si^3 |
                do2(^1 \grace {\stemup fas8(^4 \stemdown} mi8 re mi )fas |
                sol8(^5 )re^2 mi(^3 )do si(^2 )re do(^3 )la^1 |
                la2(^3 \> \! )sol4 r4 |
        }
        \context Voice \relative  do'' \repeat "volta" 2 \sequential {
                la2(^2 do8^4 si^3 la^1 si^2 |
                re8^4 )do^1 la'( sol fas mi re^1 do^3 |
                si2 re8^4 do^3 si^1 do^2 |
        }
        \bar "|.";
}

LH = \notes \sequential {
        \context Voice \relative  do' \sequential {
                <sol2 si(_3_4> <fas2 do'_1_5> |
                <sol4 )si> r4 r2 |
                <re2 la'(_1_5> <re sol_2_5> |
                <re4 )fas> r4 r2 |
                sol8(_5 re' si re sol, fa' re_2 )fa |
                sol,8( mi'_1 do_2 mi sol, do_2 la_4 )do |
                si4(_3 do re )re,_5 |
                sol4(_1 re_2 )sol, r4 |
        }
        \context Voice \relative  do \repeat "volta" 2 \sequential {
                fas8(_2^\mf re_5 fas re sol_1 re_5 sol_2 re |
                )la'4_1 r4 r2 |
                sol8(_2 re sol re la_1 re la_2 re |
        }
%       \bar "|.";
}

global = \notes {
        \key sol;
        \time 4/4;
        \tempo 4=88;
%       \bar "|.";
%       s2.* 80

}

LHInstr = "Piano ME"
RHInstr = "Piano MD"

\score {
        \context PianoStaff <
         \context Staff = treble <
                \global
                \property Staff.instrument = \RHInstr
                \property Staff.instr = " "
                \property Staff.timeSignatureStyle = "C"
                \RH
         >
         \context Staff = bass <
                \global
                \clef "F";
                \property Staff.instrument = \LHInstr
                \property Staff.instr = " "
                \property Staff.timeSignatureStyle = "C"
                \LH
         >
        >
        \paper { linewidth = 17.0\cm;
                 \translator  {
                        \OrchestralScoreContext
                        minVerticalAlign = 2.5*\staffheight;
               }
                 \translator {
                        \StaffContext
                        \consists Staff_margin_engraver;
               }
        }
%       \midi { \tempo 4 = 88; }
}