The changelog for libmpg123-dev says:
mpg123 (1.13.7-3) experimental; urgency=low
* Enable LFS aliases, attempt to fix FTBFS on kfreebsd-i386.
* Drop static library.
* Improve ARM CPUs optimizations.
-- Alessio Treglia <alessio@debian.org> Thu, 29 Mar 2012 14:13:02
+0200
Why has the static library been dropped?
urs