Lilypond takes too long to build

[Heimdall Midgard <heimdalle@gmail.com>]

The latest Debian lilypond source package (2.6.3-9) is taking too long
to build. After over a day (24 hours!) the package is still building
on my Sempron 2800+ (64 bit version running as plain i386). This is
already more than twice as long as the time it takes the behemoth
Openoffice.org to build (10+ hours), gcc-4.0 (5h 20m with tests
enabled), glibc (2h 20m) and X.org (a mere 1h 30m)

I have attempted building Lilypond on two machines with varying
configurations with the same dismal results. I aborted the build on my
Duron 1100 after 12 hours of building.

What could be the problem?

--
Albert Einstein: Phantasie ist wichtiger als Wissen, denn Wissen ist begrenzt.