perl dbi:pg

Any one care to share what it takes to get dbd:pg working?

I got the pgsql_perl5-1.9.0.tar.gz from CPAN.
I set the variables POSTGRES_LIB=/usr/local/pgsql/lib/libpq.so
and POSTGRES_INCLUDE=/path_to_/libpq-fe.h
However then it complains that it can't find postgres_ext.h

In file included from Pg.xs:16:
/install/postgresql/postgresql-snapshot/src/interfaces/libpq/libpq-fe.h:27:
postgres_ext.h: No such file or directory
make: *** [Pg.o] Error 1


respectfully,
Joseph