alternative notehead style breaks cross-staff stem

[Urs Liska]

Hi all,

I'm trying to build something like similar to an automated harmonic
display on two staves, and it seems that alternative note head styles
break the cross staff stems:

Is this known (at least not said in the NR)? Is there a way around this
issue? Note that the example code isn't necessarily the ideal approach
but a first attempt. What I eventually need is a way for a music
function to produce such a "chord" distributed on two staves, connected
by a cross-staff stem and either note head configurable in appearance.

TIA for any hints or pointers
Urs


\version "2.19.51"

\layout {
  \context {
    \PianoStaff
    \consists #Span_stem_engraver
  }
}

\score {
  <<
    \new PianoStaff <<
      \new Staff = "one" {
        s1
      }
     
      \new Staff = "two" {
        \clef bass
        <<
          \crossStaff {
            c,4 c, c, c,
          }
          \new Voice {
            \stemUp
            \change Staff = "one"
            \override NoteHead.style = #'harmonic
            e' g' bes' c''
          }
        >>
       
      }
    >>
  >>
}