Autobeaming with subdivision in 4/4

[Hugo Flordal]

Hi,
  I have problems getting autobeaming to work together with beam subdivision in
4/4 timing. I'm typesetting for the scottish snare drum and there are two
requirements that need to be fulfilled,

  * beams should always start and end on even quarters (and nowhere else), and
  * beams should be subdivided on eighths. 

  These two seem impossible to achieve simultaneously. As soon as I set
beamLength to 1/8, the beams start to break on eighths as well. Strangely it
appears to work better in other timings. 
  Below is a small example... if you comment out \set beatLength on line 15, you
see that the auto beaming is working as it should, but with \set beatLength it
breaks. What am I doing wrong?

  thanks!
   /Hugo

=================================================
\version "2.10.33"

% Header
\header {
  title = "Quarter beams with subdivision, minimal test"
  tagline = ##f
}

myautobeams = {
  #(revert-auto-beam-setting '(end 1 32 4 4)  5 8)
  #(override-auto-beam-setting '(end * * 4 4) 1 4 'Voice)
  #(override-auto-beam-setting '(end * * 4 4) 1 2 'Voice)
  #(override-auto-beam-setting '(end * * 4 4) 3 4 'Voice)
  \set subdivideBeams = ##t
  \set beatLength = #(ly:make-moment 1 8) % Subdivide beams on eighths
}

% Music
{
  %% Time
  \time 4/4   
  { 
    %% Change auto beam behaviour
    \myautobeams

        %% First measure
        \partial 8 {
        d8:32( 
        }
        \repeat volta 2 {
          d->) \times 2/3 {c16 d c} d8-> c16. d32-> c16. d32-> c d c d c8-> c 
        }
  }
}