"programming error" message on 2-bar percent repeats

[Niki Pantelias]

  Hi folks,

  I get the following error message for each repetition of a 2-bar 
phrase using \repeat "percent":

programming error: Unknown prefatory spacing.  (Continuing; cross 
thumbs)

  A one-bar percent repeat doesn't generate this message.

  Fortunately, the .ps output looks fine in either case, so I am 
assuming that the message doesn't indicate a real problem.  A score 
for full rhythm section does generate an awful lot of these messages, 
however.

  Example .ly file is pasted in below (really!).  I am using lily 
2.0.0 on RedHat 9.

  thanks,
  -- Niki


\include "english.ly"

papersize = "letter"
\include "paper20.ly"

Bass = 
 \context Voice
 \notes
 \relative c'
  {
    \key c \major
    \time 4/4
    \repeat "percent" 2 { d4 e f g | }
    \repeat "percent" 2 { a4 g f e | d c a d | }
 }

\score {
 <<
  \new Staff {
   \clef bass
   <<
    \Bass
   >>
  }
 >>
 \paper { papersize = "letter"
          linewidth = \hsize - 0.9 \in }
 }