Fuitle attempts to build LilyPond 2.8.0

[R. Mattes]

Ok, I've almost been able to build LilyPond 2.6.0
ex fontes on our Debian/Ubuntu Package builder 
using a pbuilder environment (read: strict building 
in a clean and well-defined build environment).
Unfortunately the package build process stops with
the following error message (slightly shortened where
indicated):

Renaming input to: `divisiones.ly'
Interpreting music... [7]
Preprocessing graphical objects... 
Calculating line breaks... [3][6][8]
Writing header field `texidoc' to `lily-134911652.texidoc'...
Writing header field `texidoc' to `lily-134911652.texidoc'...
Writing lily-134911652-systems.tex...
Writing lily-134911652-systems.texi...
Layout output to `lily-134911652-1.eps'...
Layout output to `lily-134911652-2.eps'...
Layout output to `lily-134911652.eps'...
Converting to PNG...
Processing 
`/tmp/buildd/lilypond-2.8.0/Documentation/user/out-www/lily-710760103.ly'
Parsing...
Interpreting music... [3]
Preprocessing graphical objects... 
Calculating line breaks... 
Writing lily-710760103-systems.tex...
Writing lily-710760103-systems.texi...
Layout output to `lily-710760103-1.eps'...
Layout output to `lily-710760103.eps'...
Converting to PNG...

Processing 
`/tmp/buildd/lilypond-2.8.0/Documentation/user/out-www/lily-2131317917.ly'
Parsing...
Interpreting music... 
programming error: Grob `NoteHead' has no interface for property `delta-pitch'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property `delta-pitch'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property `primitive'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property `primitive'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property 
`join-right-amount'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property `thickness'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property `head-width'
continuing, cross fingers
programming error: Grob `NoteHead' has no interface for property `thickness'
continuing, cross fingers

   <---x snip x--------- AND SO ON for quite a while  ---------x snip 
x-------------->

programming error: Note_spacing::get_spacing(): Common refpoint incorrect
continuing, cross fingers
programming error: Note_spacing::get_spacing(): Common refpoint incorrect
continuing, cross fingers
[2]
warning: can't find line breaking that satisfies constraints Writing
lily-2131317917-systems.tex... Writing lily-2131317917-systems.texi...
Layout output to
`lily-2131317917-1.eps'.../tmp/buildd/lilypond-2.8.0/out/share/lilypond/current/scm/framework-ps.scm:474:24:
In procedure inexact->exact in expression (inexact->exact (round #)):
/tmp/buildd/lilypond-2.8.0/out/share/lilypond/current/scm/framework-ps.scm:474:24:
Numerical overflow command failed:
/tmp/buildd/lilypond-2.8.0/lily/out/lilypond --backend=eps
--formats=ps,png --header=texidoc -I /tmp/buildd/lilypond-2.8.0/input/test
-dinternal-type-checking -danti-alias-factor=2 -dgs-font-load -I 
'/tmp/buildd/lilypond-2.8.0/Documentation/user'  -I 
'/tmp/buildd/lilypond-2.8.0/Documentation/user'  -I 
'/tmp/buildd/lilypond-2.8.0/Documentation/user/out-www'  -I 
'/tmp/buildd/lilypond-2.8.0/input'  -I 
'/tmp/buildd/lilypond-2.8.0/input/regression'  -I 
'/tmp/buildd/lilypond-2.8.0/input/test'  -I 
'/tmp/buildd/lilypond-2.8.0/input/tutorial'  -I 
'/tmp/buildd/lilypond-2.8.0/mf/out'  -I 
'/tmp/buildd/lilypond-2.8.0/mf/out' snippet-map.ly lily-908236033
lily-815435187 lily-1642467282 lily-130094515 lily-2079704915
lily-1444843630 lily-395461623 lily-1581812251 lily-1867895275
lily-1989015092 lily-653576972 lily-878352493 lily-1512613910
lily-807385207 lily-1261744467 lily-1060443014 lily-748313129
lily-2020795352 lily-669735314 lily-1901446080 lily-669840088

< ---x snip x----- LONG LIST SHORTENED -------x snip x------------------>

lily-1306675122 Child returned 2
lilypond-book.py (GNU LilyPond) @TOPLEVEL_VERSION@ make[4]: ***
[out-www/lilypond.texi] Error 1 make[4]: Leaving directory
`/tmp/buildd/lilypond-2.8.0/Documentation/user' make[3]: *** [WWW] Error 2
make[3]: Leaving directory `/tmp/buildd/lilypond-2.8.0/Documentation'
make[2]: *** [WWW] Error 2
make[2]: Leaving directory `/tmp/buildd/lilypond-2.8.0' make[1]: *** [web]
Error 2
make[1]: Leaving directory `/tmp/buildd/lilypond-2.8.0' make: ***
[build-doc-stamp] Error 2
pbuilder: Failed autobuilding of package
 -> Aborting with an error


Hmmm, anyone with an idea what's going on here? The message 
'In procedure inexact->exact in expression (inexact->exact (round #)):
/tmp/buildd/lilypond-2.8.0/out/share/lilypond/current/scm/framework-ps.scm:474:24:
Numerical overflow' just smells like Guile's rather peculiar way to report
a division by zero :-) 
Just a few notes about the used software: Ubuntu/Breezy
w.g++-4.0/guile-1.6, gs-gpl 8.50 and rather fresh mftrace  et al.

TIA Ralf Mattes