ideas:

have the configure script print out, near the end, the list of programs found
on the system that it hopes will be there also at run time, for the builder who
will also distribute the result as a package in a distribution

add M2's executable directory to PATH when running programs, and packages
wouldn't have to have a hard-coded path at all. The configure script could
detect the presence of the program, arrange for it not to be built, and print
an emphatic message requesting the package assembler to put the package
containing the program in the list of prerequisites.
