These examples are all old and don't work with the current version of
src2pkg because of using the pkgbuild and PkgBuild names. However, they
still serve as examples since othwerwise they are mostly valid for use.

change:
source /usr/libexec/pkgbuild/FUNCTIONS 
to:
source /usr/libexec/src2pkg/FUNCTIONS 

or change:
source /usr/share/Amigo/PkgBuild/FUNCTIONS
to
source /usr/libexec/src2pkg/FUNCTIONS