Frustrating issue with PGXS

Hi, 

I spent the best part of the day trying to work this out - I was working on a
system setup with PG 8.2, and wanted to work with 8.3 for development.

I installed as follows:

1. CVS checkout
2. ./configure prefix=~/install_dir
3. gmake prefix=~/install_dir
4. gmake install prefix=~/install_dir

Got a datastore up and running with initdb; created some test tables, everything
seemed to be fine. 

The problem came when I wanted to build a simple C function - I used the
following makefile: 

MODULES = example
PGXS := $(shell ~/install_dir/bin/pg_config --pgxs)
include $(PGXS)

The program compiled fine, however I noticed the compilation was refering to
files in /usr/pkg (from the 8.2 installation). I would have thought specifing
the version of pg_config from the 8.3 installation would be sufficent, but it
wasn't. 

In /lib/postgresql/pgxs/src/Makefile.global, I needed to change

PG_CONFIG = pg_config
to
PG_CONFIG = ~/install_dir/bin/pg_config

Could this have been avoided if the Makefile.global had
PG_CONFIG = $(prefix)/bin/pg_config
?


Eddie