postgres.h missing?

I can see in the source dir the include file postgres.h (src/include/postgres.h) but it doesn't exist under the installation dir (under include I only have postgres_ext.h and _fe.h).
Located a related article (http://faqchest.dynhost.com/prgm/pgsql-l/pgsql-01/pgsql-0104/pgsql-010404/pgsql01040314_23260.html) which implies that at least for the php build, postgres_fe.h should do just fine (even though the opening comments in postgres_fe.h suggest that postgres.h should be in the same dir and used instead)

Did I miss building something or should I use postgres_fe.h instead?

TIA,
thalis