app/paint-funcs/paint-funcs.c stubbed out code for using
gimp_composite.  To enable the use of gimp_composite, set the
value of gimp_composite_use_old to 0 (zero).

app/base/base.c calls gimp_composite_init() hook to initialse
all the gimp_composite "stuff."

app/composite/make-gimp-composite-dispatch.py now generates
gimp-composite-dispatch.h

app/composite/gimp-composite-dispatch.[ch] are in CVS although
they are generated files.  This is preparation for building the
table at run-time, instead of compile time.

app/composite/gimp-composite.c doesn't #include the main
dispatch table.  This is preparation for building the table at
run-time, instead of compile time.

app/composite/Makefile.am doesn't compile gimp-composite-mmx.c
(until the various remaining gcc problems and configuration issues
are worked out).